Roger de Damas (4 September 1765 – 18 September 1823) was a French Army officer and Royalist general who fought against the French Revolutionary forces in order to assist the Russian Empire and the Kingdom of Naples.
Damas was born in Paris, and in 1779 began his military career in a French regiment commanded by his uncle. In 1787 he travelled to Russia, where a large army was being prepared for the war against the Ottoman Empire, as a guest of its commander Grigory Potemkin. After gaining the latter's esteem, he fought in the naval battles against the Turks and, once land operations began, at the head of a grenadier column. Later at Saint Petersburg, he received several honours from Empress Catherine and obtained permission from the French king to fight for Russia; de Damas took part in the remainder of the Russian-Turkish war of 1789-1790, leading an army corps during the sieges of Kilia and Akerinan.
During this time the French Revolution had broken out, and de Damas joined the French Émigré armies, as aide-de-camp to the count of Artois (1791–1792). After accompanying Artois to Saint Petersburg in 1793 he joined the Émigré army of Louis Joseph, Prince of Condé serving with the Mirabeau Legion. In 1796 he was elevated to command this legion, which consisted of 1,200 men, 400 hussars and 4 artillery pieces. Damas fought in the campaigns of 1795, 1796 and 1797. In 1798 he entered the service of the King of Naples with permission of Paul I of Russia, and was given command of the 3rd Camp under Mack in the ill-fated invasion of the Roman Republic. He took command of a corps of 7,000 men, survivors of Mack’s defeat at Civita Castellana during the French counter-invasion in December 1798. His troops were driven back at Toscanella by Kellermann on 7 December, attempting to pass through Rome to re-join Mack, Damas was then intercepted by General Bonamy, who denied the validity of a safe passage for his column. Seriously wounded in the retreat, he nevertheless managed to skilfully evacuate a large part of his command from Orbetello under Naselli and reach Naples.