Jean-Philippe Rameau (September 25, 1683, Dijon – September 12, 1764) was one of the most important French composers and music theorists of the Baroque era. He replaced Jean-Baptiste Lully as the dominant composer of French opera and is also considered the leading French composer for the harpsichord of his time, alongside François Couperin.

Little is known about Rameau's early years, and it was not until the 1720s that he won fame as a major theorist of music with his Treatise on Harmony (1722). He was almost 50 before he embarked on the operatic career on which his reputation chiefly rests. His debut, Hippolyte et Aricie (1733), caused a great stir and was fiercely attacked for its revolutionary use of harmony by the supporters of Lully's style of music. Nevertheless, Rameau's pre-eminence in the field of French opera was soon acknowledged, and he was later attacked as an "establishment" composer by those who favoured Italian opera during the controversy known as the Querelle des Bouffons in the 1750s. Rameau's music had gone out of fashion by the end of the 18th century, and it was not until the 20th that serious efforts were made to revive it. Today, he enjoys renewed appreciation with performances and recordings of his music ever more frequent.

The details of Rameau's life are generally obscure, especially concerning his first forty years, before he moved to Paris for good. He was a secretive man, and even his wife knew nothing of his early life, which explains the scarcity of biographical information available. He was born on September 25, 1683 and baptised the same day. His father, Jean, worked as an organist in several churches around Dijon, and his mother, Claudine Demartinécourt, was the daughter of a notary. The couple had eleven children (five girls and six boys), of which Jean-Philippe was the seventh. Rameau was taught music before he could read or write. He was educated at the Jesuit college at Godrans, but he was not a good pupil and disrupted classes with his singing, later claiming that his passion for opera had begun at the age of twelve. Initially intended for the law, Rameau decided he wanted to be a musician, and his father sent him to Italy, where he stayed for a short while in Milan. On his return, he worked as a violinist in travelling companies and then as an organist in provincial cathedrals before moving to Paris for the first time. Here, in 1706, he published his earliest known compositions: the harpsichord works that make up his first book of Pièces de clavecin, which show the influence of his friend Louis Marchand. In 1709, he moved back to Dijon to take over his father's job as organist in the main church. The contract was for six years, but Rameau left before then and took up similar posts in Lyon and Clermont. During this period, he composed motets for church performance as well as secular cantatas. In 1722, he returned to Paris for good, and here he published his most important work of music theory, Traité de l'harmonie (Treatise on Harmony). This soon won him a great reputation, and it was followed in 1726 by his Nouveau système de musique théorique. In 1724 and 1729 (or 1730), he also published two more collections of harpsichord pieces. Rameau took his first tentative steps into composing stage music when the writer Alexis Piron asked him to provide songs for his popular comic plays written for the Paris Fairs. Four collaborations followed, beginning with L'endriague in 1723; none of the music has survived. On February 25, 1726, Rameau married the 19 year old Marie-Louise Mangot, who came from a musical family from Lyon and was a good singer and instrumentalist. The couple would have four children, two boys and two girls, and the marriage is said to have been a happy one. In spite of his fame as a music theorist, Rameau had trouble finding a post as an organist in Paris.

It was not until he was approaching 50 that Rameau decided to embark on the operatic career on which his fame as a composer mainly rests. He had already approached writer Houdar de la Motte for a libretto in 1727, but nothing came of it; he was finally inspired to try his hand at the prestigious genre of tragédie en musique after seeing Montéclair's Jephté in 1732. Rameau's Hippolyte et Aricie premiered at the Académie Royale de Musique on October 1, 1733. It was immediately recognised as the most significant opera to appear in France since the death of Lully, but audiences were split over whether this was a good thing or a bad thing. Some, such as the composer André Campra, were stunned by its originality and wealth of invention; others found its harmonic innovations discordant and saw the work as an attack on the French musical tradition. The two camps, the so-called Lullyistes and the Rameauneurs, fought a pamphlet war over the issue for the rest of the decade.

Just before this time, Rameau had made the acquaintance of powerful financier Alexandre Le Riche de La Poupelinière, who became his patron until 1753. La Pouplinière's mistress (and later, wife), Thérèse des Hayes, was Rameau's pupil and a great admirer of his music. In 1731, Rameau became the conductor of La Pouplinière's private orchestra, which was of an extremely high quality. He held the post for 22 years; he was succeeded by Johann Stamitz and then Gossec. La Pouplinière's salon enabled Rameau to meet some of the leading cultural figures of the day, including Voltaire, who soon began collaborating with the composer. Their first project, the tragédie en musique Samson, was abandoned because an opera on a religious theme by Voltaire — a notorious critic of the Church — was likely to be banned by the authorities. Meanwhile, Rameau had introduced his new musical style into the lighter genre of the opéra-ballet with the highly successful Les Indes galantes. It was followed by two tragédies en musique, Castor et Pollux (1737) and Dardanus (1739), and another opéra-ballet, Les fêtes d'Hébé (also 1739). All these operas of the 1730s are among Rameau's most highly regarded works. However, the composer followed them with six years of silence, in which the only work he produced was a new version of Dardanus (1744). The reason for this interval in the composer's creative life is unknown, although it is possible he had a falling-out with the authorities at the Académie royale de la musique.

The year 1745 was a watershed in Rameau's career. He received several commissions from the court for works to celebrate the French victory at the Battle of Fontenoy and the marriage of the Dauphin to a Spanish princess. Rameau produced his most important comic opera, Platée, as well as two collaborations with Voltaire: the opéra-ballet Le temple de la gloire and the comédie-ballet La princesse de Navarre. They gained Rameau official recognition; he was granted the title "Compositeur du Cabinet du Roi" and given a substantial pension. 1745 also saw the beginning of the bitter enmity between Rameau and Jean-Jacques Rousseau. Though best known today as a thinker, Rousseau had ambitions to be a composer. He had written an opera, Les muses galantes (inspired by Rameau's Indes galantes), but Rameau was unimpressed by this musical tribute. At the end of 1745, Voltaire and Rameau, who were busy on other works, commissioned Rousseau to turn La Princesse de Navarre into a new opera, with linking recitative called Les fêtes de Ramire. Rousseau then claimed the two had stolen the credit for the words and music he had contributed, though musicologists have been able to identify almost nothing of the piece as Rousseau's work. Nevertheless, the embittered Rousseau nursed a grudge against Rameau for the rest of his life.

Rousseau was a major participant in the second great quarrel that erupted over Rameau's work, the so-called Querelle des Bouffons of 1752–54, which pitted French tragédie en musique against Italian opera buffa. This time, Rameau was accused of being out of date and his music too complicated in comparison with the simplicity and "naturalness" of a work like Pergolesi's La serva padrona. In the mid 1750s, Rameau criticised Rousseau's contributions to the musical articles in the Encyclopédie, which led to a quarrel with the leading philosophes d'Alembert and Diderot. As a result, Rameau became a character in Diderot's then unpublished dialogue, Le neveu de Rameau (Rameau's Nephew).

In 1753, La Pouplinière took a scheming musician, Jeanne-Thérèse Goermans, as his mistress. The daughter of harpsichord maker Jacques Goermans, she went by the name of Madame de Saint-Aubin, and her opportunistic husband pushed her into the arms of the rich financier. She had La Pouplinière engage the services of the Bohemian composer Johann Stamitz, who succeeded Rameau after a breach developed between Rameau and his patron; however, by then, Rameau no longer needed La Pouplinière's financial support and protection.

Rameau pursued his activities as a theorist and composer until his death. He lived with his wife and two of his children in his large suite of rooms in Rue des Bons-Enfants, which he would leave every day, lost in thought, to take a solitary walk in the nearby gardens of the Palais-Royal or the Tuileries. Sometimes he would meet the young writer Chabanon, who noted some of Rameau's disillusioned confidential remarks: "Day by day, I'm acquiring more good taste, but I no longer have any genius" and "The imagination is worn out in my old head; it's not wise at this age wanting to practise arts that are nothing but imagination."

Rameau composed prolifically in the late 1740s and early 1750s. After that, his rate of productivity dropped off, probably due to old age and ill health, although he was still able to write another comic opera, Les Paladins, in 1760. This was due to be followed by a final tragédie en musique, Les Boréades; but for unknown reasons, the opera was never produced and had to wait until the late 20th century for a proper staging. Rameau died on September 12, 1764 after suffering from a fever. He was buried in the church of St. Eustache, Paris the following day.

While the details of his biography are vague and fragmentary, the details of Rameau's personal and family life are almost completely obscure. Rameau's music, so graceful and attractive, completely contradicts the man's public image and what we know of his character as described (or perhaps unfairly caricatured) by Diderot in his satirical novel Le Neveu de Rameau. Throughout his life, music was his consuming passion. It occupied his entire thinking; Philippe Beaussant calls him a monomaniac. Piron explained that "His heart and soul were in his harpsichord; once he had shut its lid, there was no one home." Physically, Rameau was tall and exceptionally thin, as can be seen by the sketches we have of him, including a famous portrait by Carmontelle. He had a "loud voice." His speech was difficult to understand, just like his handwriting, which was never fluent. As a man, he was secretive, solitary, irritable, proud of his own achievements (more as a theorist than as a composer), brusque with those who contradicted him, and quick to anger. It is difficult to imagine him among the leading wits, including Voltaire (to whom he bears more than a passing physical resemblance), who frequented La Pouplinière's salon; his music was his passport, and it made up for his lack of social graces.

His enemies exaggerated his faults; e.g. his supposed miserliness. In fact, it seems that his thriftiness was the result of long years spent in obscurity (when his income was uncertain and scanty) rather than part of his character, because he could also be generous. We know that he helped his nephew Jean-François when he came to Paris and also helped establish the career of Claude-Bénigne Balbastre in the capital. Furthermore, he gave his daughter Marie-Louise a considerable dowry when she became a Visitandine nun in 1750, and he paid a pension to one of his sisters when she became ill. Financial security came late to him, following the success of his stage works and the grant of a royal pension (a few months before his death, he was also ennobled and made a knight of the Ordre de Saint-Michel). But he did not change his way of life, keeping his worn-out clothes, his single pair of shoes, and his old furniture. After his death, it was discovered that he only possessed one dilapidated single-keyboard harpsichord in his rooms in Rue des Bons-Enfants, yet he also had a bag containing 1691 gold louis.