In 1806, the Republic of Ragusa (Dubrovnik) finally succumbed to French troops under general Marmont. The same year a Montenegrin force supported by the Russians tried to contest the French by seizing Boka Kotorska. The allied forces pushed the French to Ragusa. The Russians induced the Montenegrins to render aid and they proceeded to take the islands of Korčula and Brač but made no further progress, and withdrew in 1807 under the Treaty of Tilsit. The Republic of Ragusa was officially annexed to the Napoleonic Kingdom of Italy in 1808.