Louis XVIII (Louis Stanislas Xavier de France; 17 November 1755 – 16 September 1824) was King of France and Navarre from 1814 to 1824, omitting the Hundred Days in 1815. Louis XVIII spent twenty-three years in exile, from 1791 to 1814, due to the French Revolution, and was exiled again in 1815, for 100 days, upon the return of Napoleon Bonaparte from Elba. During exile he lived in several countries, including Prussia, the United Kingdom and Russia.

The French Republic abolished the monarchy and deposed King Louis XVI on 21 September 1792. Although the monarchy had been disestablished, Louis XVIII succeeded his nephew, Louis XVII, as titular King, when the latter died in prison in June 1795. For 23 years, revolution and war excluded the Bourbon line from the throne of France until 1814, when coalition armies captured Paris from Napoleon Bonaparte. Louis XVIII was restored to what he and other Royalists considered his rightful place. Louis XVIII ruled as King for slightly less than a decade, during the so-called Bourbon Restoration period. The Bourbon Restoration was a constitutional monarchy (unlike the Ancien Régime, which was absolute). As a constitutional monarchy, Louis XVIII's royal prerogative was reduced substantially by the Charter of 1814, France's new constitution. Louis had no children; therefore, upon his death, the crown passed to his younger brother, Charles, comte d’Artois. Louis XVIII was the last French monarch to die while reigning.

Louis Stanislas Xavier was born on 17 November 1755 in the Palace of Versailles, the son of Louis, Dauphin of France, and his wife, Princess Maria Josepha of Saxony. He was the grandson of the reigning King Louis XV, and as such, a Petit-fils de France. Louis Stanislas was christened Louis Stanislas Xavier six years after his birth, in accordance with Bourbon family tradition, being nameless before his baptism. The name of Louis was bestowed because it was typical of a Prince of France; Stanislas after his great-grandfather King Stanisław Leszczyński of Poland; and Xavier for Saint Francis Xavier. His mother's family held Francis Xavier as one of their patron saints. At the time of his birth, Louis Stanislas was fourth in line to the throne of France, behind his father, the Dauphin (or crown prince), and his two elder brothers, Louis Joseph Xavier, duc de Bourgogne, and Louis Auguste, duc de Berry. The former died after a horrific illness in 1761, leaving Louis Auguste as heir apparent in the next generation until the Dauphin's own premature death in 1765. The two deaths elevated Louis Stanislas to second in the line of succession, while Louis Auguste, acquired the title of Dauphin. Louis Stanislas found comfort in his governess, the comtesse de Marsan, as he was her favourite out of all her charges (Louis Stanislas' brothers and sisters). Louis Stanislas was taken away from his beloved governess when he turned seven, the age generally acknowledged as the end of infancy and the beginning of boyhood. Women could not govern a boy after they attained this age, so the role was then assumed by a male, known as a governor, duc de la Vauguyon, a friend of his father's.

Louis Stanislas was an intelligent boy, excelling in classics and literature. His education was of the same quality and consistency as that of his older brother, Louis Auguste, despite the fact that Louis Auguste was heir and Louis Stanislas was not. Louis Stanislas' education was quite religious in nature, several of his teachers being ecclesiastics. Vauguyon drilled into young Louis Stanislas and his brothers the way he thought princes should "know how to withdraw themselves, to like to work," and "to know how to reason correctly".

In April 1771, Louis Stanislas's education was formally concluded, and his own independent household was established, which astounded contemporaries with its extravagance: in 1773, the number of servants reached 390. In the same month his household was founded, Louis was granted several titles by his grandfather, Louis XV: duc d'Anjou, comte du Maine, comte de Perche and comte de Senoches. On 14 May 1771, Louis Stanislas married Princess Marie Josephine Louise of Savoy. Marie Joséphine (as she was known in France) was a daughter of the then Prince and Princess of Piedmont, future king Victor Amadeus III of Sardinia. A luxurious ball followed the wedding on 20 May. The new comtesse de Provence (Louis bore the courtesy title comte de Provence) was considered to be ugly, tedious and ignorant of the court at Versailles. Louis Stanislas was repulsed by his new wife, as was his brother the comte d'Artois, who married her sister, Princess Maria Theresa of Savoy. The marriage remained unconsummated; biographers disagree about the reason, maintaining that it was due to Louis Stanislas' alleged impotence (according to biographer Antonia Fraser) or his unwillingness to sleep with his wife, due to her poor personal hygiene. She never brushed her teeth, plucked her eyebrows, or used any perfumes. At the time of his marriage, Louis Stanislas was obese and waddled instead of walked. He never exercised and continued to eat enormous amounts of food. Despite the fact that Louis Stanislas was not infatuated with his wife, he boasted that the two enjoyed vigorous conjugal relations — such declarations were held in low esteem by courtiers at Versailles. He also proclaimed his wife to be pregnant, merely to spite Louis Auguste and his wife Maria Antonia, Archduchess of Austria, who had not yet consummated their marriage. The Dauphin and Louis Stanislas did not enjoy a harmonious relationship, and often quarreled, as did their wives. Louis Stanislas impregnated his wife in 1774, having conquered his aversion to Marie Joséphine. However, the pregnancy ended in a miscarriage.

On 27 April 1774, Louis XV fell ill after having contracted smallpox, and died the following 4 May. The Dauphin, Louis Auguste, succeeded his grandfather as King Louis XVI. Louis Stanislas longed for political influence. He attempted to gain admittance to the King’s council in 1774, ultimately failing. Louis Stanislas was left in a political limbo that he called "a gap of 12 years in my political life". Louis XVI granted Louis Stanislas revenues from the Duchy of Alençon in December 1774. The duchy was given to enhance Louis Stanislas' prestige, however his appanage turned over only 300,000 livres (livres were the currency of France from Charlemagne, to the Revolution) per annum. This was much lower than it had been at its peak in the fourteenth century. Louis Stanislas also embarked on a tour of France in 1774. He toured with his sister Madame Clotilde to meet her bridegroom Charles Emmanuel, Prince of Piedmont, heir to the throne of Sardinia, at Chambéry. In 1775, Louis Stanislas visited Lyon and his spinster aunts, Madame Adélaïde and Madame Victoire, while they were enjoying the waters at Vichy. Louis Stanislas took more tours of France than anyone else in the royal family, who rarely left the Île-de-France. The four provincial tours that Louis Stanislas took before the year 1791 amounted to a total of three months.

On 5 May 1778, Dr. Lassonne confirmed Marie Antoinette's pregnancy. On 19 December 1778, the Queen gave birth to a daughter, who was named Marie-Thérèse Charlotte de France, and given the honorific title Madame Royale. The birth of a girl came as a relief to the comte de Provence, who kept his position as heir to Louis XVI, since Salic Law excluded women from acceding to the throne of France. However, Louis Stanislas was not heir to the throne much longer. He was dislodged from the position when Marie Antoinette gave birth to a long wished-for son, Louis Joseph, on 22 October 1781. Louis Stanislas and his youngest brother, the comte d’Artois, served as godfathers by proxy for the Holy Roman Emperor, the Queen’s brother. In 1780, a new lady, Anne Nompar de Caumont de La Force, comtesse de Balbi, entered the service of Marie Joséphine. Comtemporaries judged the comtesse de Balbi to be witty and amusing, though also poorly educated and, some thought, rude. Louis Stanislas soon fell in love with his wife's new lady-in-waiting, and installed her as his mistress, which resulted in Marie Joséphine's and Louis Stanislas' already small affection for each other to cool entirely. Louis Stanislas commissioned a pavilion for his mistress on a parcel that became known as the Parc Balbi, near the Pièce d’Eau des Suisses and the Potager du Roi at Versailles.

Louis Stanislas lived a quiet and sedentary lifestyle at this point, not having a great deal to do since his self-proclaimed political exclusion in 1774. He kept himself occupied with his vast library of over 11,000 books at Balbi's pavilion. There he read for several hours each morning. However, Louis Stanislas racked up astronomical debts, and when he asked Louis XVI to pay off his debt of 10 million livres in the early 1780s, Louis XVI obliged. Louis Stanislas slid further down the line of succession when Marie Antoinette gave birth to her second son, Louis Charles, in March 1785.

An Assembly of Notables (the members consisted of magistrates, mayors, nobles and clergy) was convened in February 1787 to ratify the financial reforms sought by the Controller-General of Finance Charles Alexandre de Calonne. This provided Louis Stanislas, who abhorred the radical reforms proposed by Calonne, the opportunity he had long been waiting for to establish himself in politics. The reforms proposed a new property tax, and new elected provincial assemblies that would have a say in local taxation. Calonne's proposition was rejected outright by the notables, and, as a result, Louis XVI dismissed him. The Archbishop of Toulouse, Étienne Charles de Loménie de Brienne, acquired Calonne's ministry. Brienne attempted to salvage Calonne's reforms, but ultimately failed to convince the notables to approve them. A frustrated Louis XVI dissolved the assembly. Brienne's reforms were then submitted to the Parlement de Paris in the hopes that they would be approved. (A parlement was responsible for ratifying the King’s edicts. Each province had its own parlement, but the parlement de Paris was the most significant of all.) The Parlement de Paris refused to accept Brienne’s proposals, and pronounced that any new taxation would have to be approved by an Estates-General (the nominal parliament of France). Louis XVI and Brienne took a hostile stance against the parlement's rejection, and Louis XVI had to implement a Lit de justice (which automatically registered an edict in the Parlement de Paris) to ratify the desired reforms. On 8 May, Jean-Jacques Duval d'Eprémesnil and Goislard de Montsabert, two of the leading members of the Parlement de Paris were arrested. There was rioting in Brittany, Provence, Burgundy and Béarn in reaction to their arrest. This unrest was engineered by local magistrates and nobles, who enticed the people to revolt against the Lit de Justice, which was quite unfavourable to the nobles and magistrates. The clergy also joined the provincial cause, and condemned Brienne's tax reforms. Brienne conceded defeat in July, and agreed to calling the Estates-General to meet in 1789. He resigned from his post in August, and was replaced by the Swiss magnate Jacques Necker.

In November 1788, a second Assembly of Notables was convened by Jacques Necker, to consider the makeup of the next Estates-General. The Parlement de Paris recommended that the Estates should be the same as they were at the last assembly, in 1614 (this would mean that the clergy and nobility would have more representation than the Third Estate). The notables rejected the "dual representation" proposal. Louis Stanislas was the only notable to vote to increase the size of the Third Estate. Necker disregarded the notables' judgment, and convinced Louis XVI to grant the extra representation — Louis duly obliged on 27 December. The Estates-General were convened in May 1789 to ratify financial reforms. Louis Stanislas favoured a stalwart position against the Third Estate and its demands for tax reform. On 17 June, the Third Estate declared itself a National Assembly, an Assembly not of the Estates, but of the People. Louis Stanislas urged the King to act strongly against the declaration, while the King's popular minister, Jacques Necker, intended to compromise with the new assembly. Louis XVI was characteristically indecisive. On 9 July, the assembly declared itself a National Constituent Assembly, that would give France a Constitution. On 11 July, Louis XVI dismissed Jacques Necker, which led to widespread rioting across Paris. On 12 July, the sabre charge of Charles-Eugène de Lorraine, prince de Lambesc's cavalry regiment, the Royal-Allemand, on a crowd gathered at the Tuileries gardens, sparked the Storming of the Bastille two days later. On 16 July, the comte d’Artois left France with his wife and children, along with many other courtiers. Artois and his family took up residence in Turin, the capital city of his father-in-law’s Kingdom of Sardinia, with the Condé family. Louis Stanislas decided to remain at Versailles. When the royal family plotted to abscond from Versailles to Metz, Louis Stanislas advised the King not to leave, to which the latter duly agreed.

The royal family was ripped away from their Palace at Versailles, the day after the 5 October 1789 women's march on Versailles. In Paris, the Comte and his wife lodged in the Luxembourg Palace, while the rest of the royal family stayed in the Tuileries Palace. In March 1791, the National Assembly created a law outlining the regency of Louis Charles in case his father died while he was still too young to reign. The law created the potential regency as follows: Louis Charles' nearest male relative in France (presently the comte de Provence Louis Stanislas), and after him, the regency would be given to the duc d’Orléans, and if he were unavailable, the regency would go to election. The comte de Provence and his wife fled to the Austrian Netherlands in conjunction with the royal family’s failed Flight to Varennes in June 1791.

When the comte de Provence arrived in the Low Countries, he proclaimed himself de facto regent of France. Louis Stanislas was exploiting a document that he and Louis XVI had written before the latter's failed escape to Varennes. The document gave Louis Stanislas the regency in the event of his brother's death, or inability to perform his role as King. Louis Stanislas would join the other princes-in-exile at Coblenz soon after his escape. It was there that the comte d’Artois, the Condés and the comte de Provence, proclaimed that their objective was to invade France. Louis XVI was greatly annoyed by his brothers' behaviour. Provence sent emissaries to various European courts asking for financial aid, soldiers, and munition. Artois secured a castle for the court in exile in the Electorate of Trier, where their maternal uncle, Clemens Wenceslaus of Saxony, was the Archbishop-Elector. Louis Stanislas' rallying bore fruit when the rulers of Prussia and Austria gathered at Dresden. They released the Declaration of Pillnitz in August 1791, which urged Europe to intervene in France if Louis XVI or his family were threatened. Provence's endorsement of the declaration was not well received in France, by the people, or by Louis XVI.

In January 1792, the Legislative Assembly declared that all the émigrés were traitors to France. Their property and titles were confiscated. The monarchy of France was abolished by the National Convention on 21 September 1792. Louis XVI was executed in January 1793. This left his young son, Louis Charles, as titular King Louis XVII of France. The princes-in-exile proclaimed Louis Charles "King Louis XVII". Louis Stanislas now unilaterally declared himself regent for his nephew, who was too young to be head of the House of Bourbon (since the French monarchy had been abolished for several months, Louis XVII never actually ruled, and any claim to regency would have been in name only.) Young Louis XVII's reign did not last long as he died in June 1795, survived by his sister Marie-Thérèse Charlotte de France, Madame Royale. On 16 June, the princes-in-exile declared the comte de Provence "King Louis XVIII". The new King accepted their declaration soon after. Louis XVIII busied himself drafting a manifesto in response to Louis XVII's death. The manifesto, known as "The Declaration of Verona" was Louis XVIII's attempt to introduce the French people to his politics (after all, he had just been declared King by the exiles). The Declaration of Verona beckoned France back into the arms of the monarchy, "which for fourteen centuries was the glory of France". Louis XVIII negotiated Marie-Thérèse’s release from her Paris' prison in 1795. Louis XVIII desperately wanted Marie-Thérèse to marry her first cousin, Louis Antoine, duc d’Angoulême, the son of the comte d'Artois. Louis XVIII deceived his niece by telling her that her parents' last wishes were for her to marry Louis Antoine, and Marie-Thérèse duly agreed to her uncle-king's wishes. Louis XVIII was forced to abandon Verona when Napoleon Bonaparte invaded the Republic of Venice.

Louis XVIII had been vying for the custody of his niece Marie-Thérèse since her release from the Temple Tower in December 1795. Louis succeeded when Francis II, Holy Roman Emperor agreed to relinquish custody of Marie-Thérèse in 1796. She had been staying in Vienna with her Habsburg relatives since January 1796. Louis XVIII moved to Blankenburg in Duchy of Brunswick [Braunschweig] after his departure from Verona. He lived in a modest two-bedroom apartment over a shop. Louis XVIII was forced to leave Blankenberg when King Frederick William II of Prussia died. In light of this, Marie-Thérèse decided to wait a while longer before reuniting with her uncle. In 1798, Emperor Paul I of Russia offered Louis the use of Jelgava Palace in Courland (now Latvia). Paul I also guaranteed Louis's safety and bestowed upon him a generous pension, however, the Emperor later disregarded this allowance. Marie-Thérèse finally joined Louis XVIII at Jelgava in 1799. In the winter of 1798–1799, Louis XVIII wrote a biography on Marie Antoinette, titled Réflexions Historiques sur Marie Antoinette. King Louis attempted to recreate the court life of Versailles at Jelgava, where many old courtiers lived, reestablishing all the court ceremonies, including the lever and coucher (these ceremonies were for waking and bedding respectively).

Marie-Thérèse married her cousin Louis Antoine on 9 June 1799, at Jelgava Palace. Louis XVIII ordered his wife to attend the marriage proceedings in Courland without her long-time friend (and rumoured lover) Madame de Gourbillon. Queen Marie Joséphine lived apart from her husband in Schleswig Holstein. Louis XVIII was trying desperately to display to the world a united family front. The Queen refused to leave her friend behind and drama ensued, rivalling the wedding in notoriety. Louis XVIII knew that his nephew Louis Antoine was not compatible with Marie-Thérèse. Despite this, he still rallied for their marriage, which proved to be quite unhappy and produced no children. Louis XVIII attempted to strike up a correspondence with Napoleon Bonaparte (First Consul of France) in 1800. Louis XVIII besought Bonaparte to restore the Bourbons to their throne, but the future emperor was immune to Louis's requests and continued to consolidate his position as ruler of France. Louis XVIII encouraged his niece to write her memoirs, as he wished them to be used as Bourbon propaganda. Louis also used the diaries of Louis XVI' final attendants in the same way, in 1796 and in 1803. In January 1801, Tsar Paul told Louis XVIII that he could no longer live in Russia. The court at Jelgava was so low on funds that they had to auction some of their possessions to afford the journey out of Russia. Marie-Thérèse even sold a diamond necklace that the Emperor Paul had given her as a wedding gift.

Marie-Thérèse convinced Queen Louise of Prussia to give her family refuge in Prussian territory. Louise consented, but the Bourbons were forced to assume pseudonyms. With Louis XVIII using the title Comte d'Isle (named after his estate in Languedoc), he and his family assumed residence in Warsaw in the Lazienki Palace from 1801 to 1804, after an arduous voyage from Jelgava. It was very soon after their arrival that they learned of the death of Paul I. Louis hoped that Paul's successor, Alexander I of Russia, would repudiate his father's banishment of the Bourbons. Louis XVIII then intended to set off to the Neapolitan court. The comte d’Artois asked Louis to send his son, Louis Antoine, and daughter-in-law, Marie-Thérèse, to him in Edinburgh. Louis was distressed by Artois' request, as Louis Antoine and his wife were all that he had, while Charles had an allowance from King George III of Great Britain. Louis XVIII's court in exile was being spied on by French police. Louis greatly valued his niece's advice. The court-in-exile was being financed by interest owed from Francis II on valuables his aunt, Marie Antoinette, had removed from France. The comte d'Artois in England also sent money. They had to cut their expenses significantly.

In 1803, Napoleon tried to force Louis XVIII to renounce his right to the throne of France, but Louis refused. In May 1804, Napoleon Bonaparte declared himself Emperor of the French. Louis XVIII and his nephew departed for Sweden in July for a Bourbon family conference, where Louis XVIII, the comte d’Artois, and the duc d'Angoulême issued a statement condemning Napoleon's decision to declare himself emperor. The King of Prussia issued a proclamation saying that Louis XVIII would have to leave Prussian territory, which meant leaving Warsaw. Alexander I of Russia invited Louis XVIII to resume residence in Jelgava. Louis XVIII had to live under less generous conditions than those enjoyed under Paul I, and he intended to embark for England as soon as possible.

Louis XVIII created another policy in 1805; a declaration that was far more liberal than his former ones. It repudiated his Declaration of Verona, promised to abolish conscription, keep Napoleon I's administrative and judicial system, reduce taxes, eliminate political prisons, and guarantee amnesty to everyone who did not oppose a Bourbon Restoration. The opinions expressed in the declaration were largely those of the comte d’Avaray (Louis's best friend in exile).

Louis XVIII was forced once again to leave Jelgava when Alexander of Russia informed him that his safety could not be guaranteed on continental Europe. In July 1807, Louis boarded a Swedish frigate to Stockholm, bringing with him only the duc d'Angoulême. Louis did not stay in Sweden for long, and arrived in Great Yarmouth, Norfolk, England, in November 1807. He took up residence in Gosfield Hall, leased to him by the Marquess of Buckingham. Louis brought his wife and Queen, Marie Joséphine, from the continent in 1808. Louis's stay at Gosfield Hall did not last long, and he moved to Hartwell House in Buckinghamshire, where over one hundred courtiers were housed. The King paid £500 in rent each year to the proprietor, Sir George Lee. The Prince Regent of the United Kingdom was very charitable to the exiled Bourbons, granting them permanent asylum and giving them extremely generous allowances. The comte d'Artois did not join the court-in-exile in Hartwell, continuing his frivolous life in London. Louis' friend the comte d'Avaray left Hartwell for Madeira in 1809, and died there in 1811. Louis replaced Avaray with the Comte de Blacas. Louis XVIII's wife, Queen Marie Joséphine, died on 13 November 1810. That same winter, Louis suffered a particularly severe case of gout, which was a recurring problem for him at Hartwell, and he had to be put in a wheelchair.

Napoleon I embarked on an invasion of Russia in 1812. This war would prove to be the turning point in his fortunes, as the expedition failed miserably and Napoleon was forced to retreat with an army in tatters. In 1813, Louis XVIII issued another declaration while at Hartwell. "The Declaration of Hartwell" was more liberal than his "Declaration of 1805", asserting that all those who served Napoleon or the Republic would not have repercussions for their acts, and that the original owners of the Biens nationaux (lands confiscated from the nobles and clergy during the Revolution) were to be compensated for their losses. Allied troops entered Paris on 31 March 1814. Louis was, however, unable to walk, and so sent the comte d'Artois to France in January 1814. Louis XVIII issued letters patent appointing Artois Lieutenant General of the Kingdom in the event of the Bourbons being restored. Napoleon I abdicated on 11 April, five days after his Senate had invited the Bourbons to re-assume the throne of France. The comte d'Artois ruled as Lieutenant-General of the Kingdom, until his brother's arrival in Paris on 3 May. Upon his return, the King displayed himself to his subjects by creating a procession through the city. He took up residence in the Tuileries Palace the same day. His niece, the duchesse d'Angoulême, fainted at the sight of the Tuileries.

Napoleon's senate called Louis XVIII to the throne on the condition that he would accept the new constitution, which entailed recognition of the Republic and the Empire, a bicameral parliament elected every year, and the tri-colour flag of the aforementioned regimes. Louis XVIII opposed the senate's constitution, and stated that he was "disbanding the current senate in all the crimes of Bonaparte, and appealing to the French people". The senatorial constitution was burned in a theatre in royalist Bordeaux, and the Municipal Council of Lyon voted for a speech that defamed the senate. The armies occupying Paris demanded that Louis XVIII implement a constitution. The Charter of 1814 that Louis created entailed all that Saint-Ouen wished for and more: Freedom of Religion, a legislature composed of the Chamber of Deputies and the Chamber of Peers, the press would enjoy a degree of freedom, the biens nationaux, would remain in the hands of their current owners. The constitution had 76 articles. Taxation was to be voted on by the chambers. Catholicism was the official religion of France. To be eligible for election to the Chamber of Deputies, one had to pay over 1,000 francs per year in tax, and be over the age of forty. The King appointed peers to the Chamber of Peers on a hereditary basis, or for life at his discretion. Deputies were elected every five years, with one fifth of them up for election each year. There were 90,000 citizens eligible to vote.

Louis XVIII signed the Treaty of Paris on 30 May 1814. The treaty gave France her 1792 borders, which extended east of the Rhine. She had to pay no war indemnity, and the occupying armies of the Sixth Coalition withdrew instantly from French soil. These generous terms would be reversed in the next Treaty of Paris after the Hundred Days (Napoleon's return to France in 1815).

It did not take Louis XVIII long to go back on one of his many promises. He and his Controller-General of Finance Baron Louis were determined not to let the exchequer fall into deficit (there was a 75 million franc debt inherited from Napoleon I), and took fiscal measures to ensure this. Louis XVIII assured the French that the unpopular tax on tobacco, wine and salt would be abolished when he was restored, but he failed to do so, which led to rioting in Bordeaux. Expenditure on the army was slashed in the 1815 budget — in 1814, the military had accounted for 55% of government spending.

Louis XVIII admitted the comte d'Artois and his nephews, the duc d'Angoulême, and the duc de Berry into the King's council in May 1814, upon its establishment. The council was informally headed by the Prince de Talleyrand. Louis XVIII took a large interest in the goings-on of the Congress of Vienna (set up to redraw the map of Europe after Napoleon's demise). Talleyrand represented France at the proceedings. Louis was horrified by Prussia's intention to annex the Kingdom of Saxony, to which he was attached because his mother was born a Saxon princess, and he was also concerned that Prussia would dominate Germany. He also wished the Duchy of Parma to be restored to the Parmese Bourbons, and not to Empress Marie Louise of France, as was being suggested by the Allies. Louis also protested the Allies' inaction in Naples, where he wanted the Napoleonic usurper Joachim Murat removed in favour of the Neapolitan Bourbons, who had ruled for centuries. On behalf of the Allies, Austria agreed to send a force to the Two Sicilies to depose Murat in February 1815, when it became apparent that Murat corresponded with Napoleon I, which was explicitly forbidden by a recent treaty. Murat never actually wrote to Napoleon, but Louis, intent on restoring the Neapolitan Bourbons at any cost, forged the correspondence, and subsidised the Austrian expedition with 25 million francs. Louis XVIII succeeded in getting the Neapolitan Bourbons restored immediately. Parma was bestowed upon Empress Marie Louise for life, and the Parmese Bourbons were given the Duchy of Lucca until the death of Marie Louise.

On 26 February 1815, Napoleon Bonaparte escaped his island prison of Elba and embarked for France. He arrived with about 1,000 troops near Cannes on 1 March. Louis XVIII was not particularly worried by Bonaparte's excursion, as such small numbers of troops could be easily overcome. There was, however, a major underlying problem for the Bourbons: Louis XVIII had failed to purge the military of its Bonapartist troops. This led to mass desertions from the Bourbon armies to Bonaparte's. Furthermore, Louis XVIII could not join the campaign against Napoleon in the south of France because he was suffering from another case of gout. Minister of War Marshall Soult dispatched Louis Philippe d'Orléans, the comte d'Artois and Marshall MacDonald to apprehend Napoleon. Louis XVIII's underestimation of Bonaparte proved disastrous. On 19 March, the army stationed outside Paris defected to Bonaparte, leaving the city vulnerable to attack. That same day, Louis XVIII quit the capital with a small escort at midnight. Louis decided to go first to Lille, and then crossed the border into the United Kingdom of the Netherlands, staying in Ghent. Other leaders, most prominently Alexander I of Russia, debated that in case of a second victory over the French Empire, the First Prince of the Blood Louis Philippe d'Orléans should be proclaimed king instead of Louis XVIII. However, Napoleon did not rule France again for very long, suffering a decisive defeat at the hands of the Duke of Wellington at the Battle of Waterloo on 15 June. Leaders came to the consensus that Louis XVIII should be restored to the throne of France.

Louis XVIII returned to France promptly after Napoleon's defeat, to ensure his second restoration "in baggage train of the enemy", i.e. with Wellington's troops. The Duke of Wellington used King Louis' person to open up the route to Paris, as some fortresses refused to surrender to the Allies, but agreed to do so for their King. King Louis arrived at Cambrai on 26 June, where he released a proclamation stating that all those who served the Emperor in the Hundred Days would not be persecuted, except for the "instigators". It was also acknowledged that Louis XVIII's government might have made mistakes during the First Restoration. On 29 June, a deputation of five from the Chamber of Deputies and the Chamber of Peers approached Wellington about putting a foreign Prince on the throne of France. Wellington rejected their pleas outright, declaring that "[Louis XVIII is] the best way to preserve the integrity of France". Wellington ordered the deputies to espouse King Louis' cause. Louis XVIII entered Paris on 8 July to a boisterous reception: the Tuileries Palace gardens were thronged with bystanders, and, according to the Duke of Wellington, the acclamation of the crowds there were so loud that evening, that he could not converse with the King.

Louis XVIII's role in politics from the Hundred Days onward was voluntarily diminished, he resigned most of his duties to his council. He and his ministry embarked on a series of reforms through the summer of 1815. The King's council, an informal group of ministers that advised Louis XVIII, was dissolved and replaced by a tighter knit privy council, the "Ministère de Roi". Artois, Berry and Angoulême were purged from the new "ministère", and Talleyrand was appointed as the first Président du Conseil, i.e. Prime Minister of France. On 14 July, the ministry dissolved the units of the army deemed "rebellious". Hereditary peerage was re-established to Louis' behest by the ministry. In August, elections for the Chamber of Deputies returned unfavourable results for Talleyrand. The ministry wished for moderate deputies, but the electorate voted almost exclusively for ultra-royalists, resulting in the Chambre introuvable. The duchesse d'Angoulême and the comte d'Artois pressured King for the dismissal of his obsolete ministry. Talleyrand tendered his resignation on 20 September. Louis XVIII chose Armand-Emmanuel du Plessis, duc de Richelieu to be his new Prime Minister. Richelieu was chosen because he was accepted by Louis' family and the reactionary Chamber of Deputies. Anti-Napoleonic sentiment was high in Southern France, and this was prominently displayed in the White Terror. The White Terror saw the purge of all important Napoleonic officials from government, and the execution of others. The people of France committed barbarous acts against some of these officials. Guillaume Marie Anne Brune (a Napoleonic marshal) was savagely assassinated, and his remains thrown into the Rhône River. Louis XVIII deplored such illegal acts, but vehemently supported the prosecution of those marshals that helped Napoleon I in the Hundred Days. Louis XVIII’s government executed Napoleon's Marshal Ney, Prince de la Moskowa, in December 1815 for treason. His confidants the Marquis de Bonnay and the Duc de la Chatre advised him to inflict firm punishments on the “traitors”. The King was reluctant to shed blood, and this greatly irritated the ultra-reactionary chamber of deputies, who felt that Louis XVIII was not executing enough. The government issued a proclamation of amnesty to the “traitors” in January 1816, but the trials that had already begun were finished in due course. That same declaration also banned any member of the House of Bonaparte from owning property in, or entering, France. It is estimated that between 50,000 – 80,000 officials were purged from the government during what was known as the Second White Terror.

In November 1815, Louis XVIII’s government had to sign another Treaty of Paris, formally ending Napoleon’s hundred days. The previous treaty had been quite favourable to France, but this one took a hard-line. France’s borders were retracted to their extent at 1790. France had to pay for an army to occupy her, for at least five years, at a cost of 150 million francs per year. France also had to pay a war indemnity of 700 million francs to the allies. In 1818, the Chambers passed a military law, which increased the size of the army by over 100,000. In October of the same year, Louis XVIII’s foreign minister, the Duc de Richelieu, succeeded in convincing the powers to withdraw their armies early, in exchange for a sum of over 200 million francs. Louis XVIII chose many centrist cabinets, as he wanted to appease the populace. Much to the dismay of his brother, the ultra-royalist comte d’Artois, he always dreaded the day he would die, believing that his brother, and heir, Artois, would abandon the centrist government for an ultra-royalist autocracy, which would not bring favourable results. King Louis disliked the First Prince of the Blood, Louis-Philippe d'Orléans, and took every opportunity to snub him. King Louis' nephew, the duc de Berry, was assassinated at the Paris Opera, on 14 February 1820. The royal family was grief-stricken and Louis XVIII broke an ancient tradition to attend his nephew's funeral, as previous Kings of France could not have any association with death.

Berry was the only member of the family thought to be able to beget children. His wife gave birth to a posthumous son in September, Henri, duc de Bordeaux. The future of the Bourbons as kings of France was in still doubt. The Chamber of Deputies proposed amending the Salic law to allow the Duchesse d’Angoulême to accede to the throne. On 12 June 1820, the Chambers ratified legislation that increased the number of deputies from 258 to 430. The extra deputies were to be elected by the wealthiest quarter of the population in each department. These individuals now effectively had two votes. Around the same time as the “law of the two votes”, Louis XVIII began to receive visits every Wednesday from a lady named Zoé Talon, comtesse du Cayla, and ordered that nobody should disturb him while he was with her. It was rumoured that he inhaled snuff from her breasts, which earned her the nickname of tabatière (snuffbox). In 1823, France embarked on a military intervention in Spain, where a revolt had occurred against the King Ferdinand VII. France succeeded in crushing the rebellion, which the duc d’Angoulême headed.

Louis XVIII's health began to fail in spring 1824. He was suffering from obesity and gangrene, both dry and wet. Louis died on 16 September 1824, surrounded by the extended royal family and some government officials. He was succeeded by his youngest brother, the comte d’Artois, as Charles X. Louis XVIII was the only French monarch of the 19th century to die while still ruling. He was interred at the Basilica of St Denis, the necropolis of French kings.