Dagobert Sigismund, Count Wurmser (7 May 1724 – 22 August 1797) was an Austrian field marshal during the French Revolutionary Wars. Although he fought in the Seven Years War, the War of the Bavarian Succession, and mounted several successful campaigns in the Rhineland in the initial years of the French Revolutionary Wars, he is probably most remembered for his unsuccessful operations against Napoleon Bonaparte during the 1796 campaign in Italy.

Although initially in the Army of France during the Seven Years War, Wurmser left France after Louis reached a peace agreement with Britain, and joined the military of the House of Habsburg. He later took part in the short-lived War of the Bavarian Succession, also called the Kartoffelkrieg (Potato War). During the French Revolutionary Wars, Wurmser commanded several imperial Habsburg armies in the Rhine River valley between 1793 and 1795, and perhaps his most conspicuous achievement was the taking of the lines of Lauterburg and Weissenburg in October 1793. In 1796, Francis II, Holy Roman Emperor, sent him to northern Italy, where the Habsburg military defended Austria's southern territories. In a series of well-fought battles with the French army, under the command of the up and coming general Napoleon Bonaparte, Wurmser was trapped with his army in Mantua; after a negotiated capitulation, Wurmser left the city with his honors and 700 men, and marched back to Vienna. His defeat at Mantua did not diminish the luster of his service in imperial eyes — he was granted another appointment immediately — but he was an old man of 72 years who had spent most of his adult life in arduous campaigning. His health failed him shortly after his appointment and he died in 1797.

Born in either the commune of Bas Rhin, in the village of Sélestat, or in Strasbourg, in Alsatia, Wurmser first served in the French army during the early campaigns of the Silesian Wars as a cavalry officer under command of Marshal Charles de Rohan, prince de Soubise. In 1747, he was promoted to Captain of Cavalry.

In 1750, when his father left Alsace and became a Habsburg subject, Wurmser too left French service and joined the House of Habsburg military. He brought with him the legions he commanded from France. As part of the imperial Austrian army, he participated in the last years of the continental war, sometimes called the Little War, so called, because it did not involve three of the five great powers involved. In these engagements against the Prussians, he showed exceptional command capabilities and a wily and courageous attitude. On 30 January 1761, Emperor Francis I raised him to comital status of the Holy Roman Empire of the German Nation. Two years later, Archduke Charles of Lothringen, the Statthalter of Netherlands, known as an audacious partisan collected his volunteers — a regiment each of Infantry and Hussars, with an artillery company — and joined Austrian service.

In Spring 1778, Wurmser's 30th Hussars were posted in northern Bohemia, to cover the Border with Saxony and Silesia. Friedrich von Nauendorf, the son of the previous Colonel-Proprietor of the Regiment, was a captain in a village outpost, with about 50 Hussars under his command. In early July, the Prussian General Johann Jakob von Wunsch (1717 – 1788), crossed into Bohemia near the fortified town of Náchod, in the opening action of the War of Bavarian Succession. Nauendorf led his 50 Hussars to engage Wunsch's considerably larger force. When they encountered Wunch's force, he greeted them as friends; by the time the Prussians realized the allegiance of the Hussars, Nauendorf and his small force had the upper hand, and Wunsch withdrew. The next day Nauendorf was promoted to major. As the war evolved over the summer, Wurmser's Hussars covered the left flank of the main army, which was positioned in the entrenched heights above Jaroměř, in a triple line of redoubts extending 15 kilometers (9 mi) along the river to Königgrätz. In October, Joseph II, Holy Roman Emperor, withdrew most of the imperial army to the Bohemian border, under threat of intervention by Catherine II of Russia; Frederick II of Prussia did the same. A small force of hussars and dragoons remained in Bohemia to provide a winter cordon, designed to prevent Prussian incursions into Bohemia. Appointed to be commander of the winter cordon, Wurmser ordered a small assault column under command of Colonel Wilhelm Klebeck to attack the village of Dittersbach. Klebeck led a column of Croats into the village. During the action, 400 Prussians were killed, another 400 made prisoner, and eight colors were captured. Following his successes against the Prussians in 1778, Joseph awarded him the Knights Cross of the Military Order of Maria Theresa on 21 October 1778.

In another raid, in January 1779, Wurmser advanced into the County of Glatz in five columns, two of which, commanded by Major General Franz Joseph, Count Kinsky, surrounded Habelschwerdt on 17–18 January. While one column secured the approach, the other, under the leadership of Colonel Pallavicini, stormed the village, captured the Prince of Hessen-Philippsthal and 700 men, three cannons and seven colors. Wurmser himself led the third column in an assault on the so-called Swedish blockhouse at Oberschwedeldorf; it and the village of Habelschwerdt were set on fire by howitzers. Major General Ludwig, Baron of Terzi (1730 – 1800), who was covering with the remaining two columns, threw back the enemy relief and took 300 Prussian prisoners. Meanwhile, Wurmser maintained his position at the nearby villages of Rückerts and Reinerz. His forward patrols reached the outskirts of Glatz, and were able to cover the Silesian borders, almost reaching Schweidnitz. Halberschwerdt and Oberschedeldorf were both destroyed.

In 1787, Wurmser received a promotion to General of Cavalry; he held a series of posts in Vienna, Bohemia and Galicia, becoming Commanding General at the latter in 1787 during the Austrian War with the Ottoman Empire. While Wurmser fought Austria's battles in the Balkans, in France, a coalition of the clergy and the professional and bourgeoisie class — the First and Third estates — led a call for reform of the French government and the creation of a written constitution. Initially, the rulers of Europe viewed the French Revolution as an event between the French king and his subjects, and not something in which they should interfere. In 1790, Leopold succeeded his brother Joseph as emperor and by 1791, he considered the situation surrounding his sister, Marie Antoinette, and her children, with greater alarm. In August 1791, in consultation with French émigré nobles and Frederick William II of Prussia, he issued the Declaration of Pilnitz, in which they declared the interest of the monarchs of Europe as one with the interests of Louis and his family. They threatened ambiguous, but quite serious, consequences if anything should happen to the royal family. The French émigrés continued to agitate for support of a counter-revolution. On 20 April 1792, the French National Convention declared war on Austria. In the War of the First Coalition (1792 – 1797), France opposed most of the European states sharing land or water borders with her, plus Portugal and the Ottoman Empire.

From February 1793 to January 1794, Wurmser commanded the imperial Army of the Rhine. He commanded the successful storming of the Lauterburg and Weissenburg lines on 13 October 1793. The Lines, a series of earth works on the south side of the Lauter river, a tributary of the Rhine river in Alsace-Lorraine, offered a major strategic defensive position for the French. Part of France's Army of the Vosges, under general command of Jean Victor Moreau, manned the French position. The three battalions and six squadrons, commanded by General of Brigade Illier, held the position with ten artillery pieces. The French defensive line ran west from Lauterbourg on the Rhine to Saarbrucken. The western part of this line, from Lauterbourg to Wissembourg , was protected by the Lines of Wissembourg, a series of fortifications built nearly a century earlier to protect Alsace from invasion along the flat plain between the Vosges and the Rhine. The Army of the Rhine defended the Lines, the Army of the Rhine was at Saarbrucken and the Corps of the Vosges linked the two, with camps at Hornbach and Kettrick.

On 20 August, Wurmser directed the 4th Allied Column, and Field Marshal Kavanagh's Hessen and Austrian troops, augmented by a battalion of Emigre troops, to assault part of the works; Kavanagh's attack successfully ousted the French from the position; General Illier was killed by a Hessen Jäger. An unknown number of the 3,000 French defenders were killed or wounded; three officers and 100 men were captured. The testing for the Weissembourg Lines continued for the next 45 days. Each skirmish, each probe, tested the French strength and resolve. In mid-September the Prussians successfully defeated a French assault on Pirmasens, a small fortification to the north and east; this success encouraged the Austrian and Prussian alliance to venture a major assault on the French defenses. Wurmser's force of 33,599 infantry and 9,635 cavalry had whittled away at the Lines, skirmishing throughout August and September with French infantry and cavalry, which always withdrew to the superior defensive position behind the earthen works. While the Prussians marched around the lines, from Pirmasens, Wurmser organized his force into seven columns, and they assaulted the Lines in waves, beginning on 13 September. Wurmser had commanded the Austrian contingent at the defeat at the Battle of Weissenburg, on 26 December 1793.

From August 1795 to June 1796, Wurmser commanded the Army of the Upper Rhine. In 1796, Wurmser descended into northern Italy, with 25,000 men from his old Army of the Rhine, to unite with Beulieu's battered army of northern Italy. The two armies met at Trent, and marched to Mantua in three columns. Wurmser's columns scored some initial successes. The forward column, under command of Peter Quasdanovich moved toward Lake Garda, and a small reconnaissance force under Johann von Klenau advanced from the alps on the city of Brescia; there, they found the local French garrison unprepared. At midnight, Klenau led two squadrons of the Wurmser 8th Hussar Regiment and several other battalions and squadrons in an attack on the French garrison. They captured 600 – 700 French soldiers stationed there and three officials of the French Directory: Jean Lannes, Joachim Murat, and François Étienne de Kellermann. Quasdanovich managed to occupy Lonato.

Wurmser did not count on swift movement by the French. Within two days, Klenau's force retreated in the face of Napoleon Bonaparte and 12,000 Frenchmen; his small advance guard was quickly pushed out of Brescia on 1 August. At the subsequent Battle of Lonato of 2–3 August 1796, the French also forced Quasdanovich's column to withdraw into the mountains, with heavy losses. The mopping up operations lasted until mid August, isolated Quasdanovich's force by Lake Garda, and freed the French to concentrate on Wurmser's main force at Castiglione delle Stiviere, further south; Bonaparte's subsequent victory against Wurmser at the Battle of Castiglione forced the old commander across the Mincio River and allowed the French to return to the siege of Mantua.

The resumed siege was not without its problems. To move swiftly against Wurmser, Napoleon had abandoned all his siege equipment, leaving it at Mantua. When he resumed the siege, it was much less effective without his guns. Furthermore, by early September, many of the scattered Austrian units had rejoined Wurmser's column. Even so, at the Battle of Bassano on 8 September, the Austrians were outnumbered almost two to one by the French. As the Austrian army retreated, Bonaparte ordered a pursuit that caused the Austrians to abandon their artillery and baggage. Most of the third battalion of the 59th Jordis, and the first battalion of the Border Infantry Banat were captured and these units ceased to exist after this battle. The Austrians lost 600 killed and wounded, and 2,000 captured, plus lost 30 guns, eight colors, and 200 limbers and ammunition wagons. Wurmser's column fought its way to besieged Mantua, but emerged suddenly, in an effort to escape, at the Battle of La Favorita near there on 15 September. This was the second attempt to relieve the fortress; as the Austrians withdrew from the battle, they retreated into Mantua itself, and from 15 September until 2 February 1797, Wurmser was trapped inside the fortress while the city was besieged.

Following the Austrian loss at the Battle of Rivoli, 48 kilometers (30 mi) north of Mantua, on 14–15 January 1797, when clearly there would be no Austrian relief for Mantua, Wurmser sent one of his juniors, Johann von Klenau, to negotiate conditions of surrender with French General Jean Sérurier. Additional evidence suggests that Bonaparte was present and dictated far more generous terms than the Austrians expected. Wurmser, who Napoleon held in high esteem, left Mantua with his men and officers, and his battle honors, and marched back to Austrian lands.

Of all the field marshals in Habsburg service during the French Revolutionary and Napoleonic Wars, Wurmser was recognized among the best. Some historians attribute Austrian problems to its aging general staff, compared to the relatively young general staff of the French Empire. Certainly the Habsburg military was well-endowed with an experienced, graying staff. Wurmser at 72, approaching 73 in the 1796 campaign, Bellegarde, Peter Quasdanovich (b. 1738) was nearing 70. Despite the graying general staff, there were also youngsters, and these demonstrated acute military acumen: Archduke Charles was 26 years old in the 1796 campaign and had been tutored by Hohenlohe-Kirchberg and Wurmser; Schwarzenberg was also young, under 30; Johann von Klenau, at 31, was the youngest field Marshal in the Habsburg military; and there were many others. Wurmser may have been hampered more by the Aulic Council than by his age; Digby Smith points out that he descended into Italy fettered with a new and inexperienced chief of staff sent to him by the Council with battle plans and instructions in writing. These restricted his movements in Italy, preventing him from responding to targets of opportunity.

A knight without fear and above reproach. Broken in health, Wurmser died in Vienna the following summer.