Count Louis Alexandre Andrault de Langeron was one of many French émigrés in the Russian service. He was born in Paris on 24 January 1763, into a French noble family. His first experience of battle was in the American War of Independence. He then served at Caracas and Saint Domingo in 1782 - 1783, before being promoted up the ranks in the French army to colonel of the Armagnac Regiment in 1788. Langeron joined the Russian Army besieging the Ottoman Fortress of Izmail in 1790. He was awarded a golden sword for his courage and enterprise during the siege, and he remained in the Russian service for the rest of his life.
Langeron went on to serve in the Prince of Saxony-Teschen's Army against the French in the Netherlands, before being sent as a military observer to the Austrian Army in Northern France and the Netherlands in 1793 - 1794. Langeron then transferred to the Malorossiisk Grenadiers Regiment in August 1795, before being promoted to brigadier and then major general and chef of the Ufa Musketeer Regiment by 2 June 1797. He was later given the title count of the Russian Empire by Emperor Paul. On 24 August 1800, he became head of the infantry troops of the Brest-Litovsk Inspection.
Langeron participated in the Battle of Austerlitz in the 1805 campaign, in which his poor performance almost cost him his career. He was disgraced and sent to Odessa. He subsequently redeemed himself fighting against the Ottomans from 1806 - 1811. On 19 August he became head of the 22nd Division, and took part in the Battle of Ruse in 1811, which hastened his promotion to general of infantry on 3 September.
Langeron did not feature prominently in the 1812 campaign, and was much more heavily involved in the later campaigns against Napoleon in continental Europe. Nevertheless he commanded the 1st Corps of the Army of the Danube, and saw action at Brest-Litovsk and at Berezina. In 1813 he was the senior Russian officer in Blücher's Russo-Prussian Army. He excellently directed the blockade of Torun (Thorn), a major fortress commanding a key crossing of the Vistula that was blocking all use of the river of the river for transporting supplies. Langeron also took part in many of the battles of 1813, notably Bautzen, Lowenberg, Katzbach, and Leipzig.
In the 1814 campaign Langeron was also very active, fighting at Soissons, Craonne, Laon, Rheims, Le Fère Champenoise and storming Paris from the North, through Montmartre. During the Hundred Days he led his army from the Rhine to Alsace Lorraine where his men blockaded the fortresses there until the capitulation after Waterloo.
Count Langeron subsequently returned to Russia and was appointed Military Governor of various provinces, including Odessa. He was relieved of his duties on 26 May due to poor health, and travelled to France in the following two years. Yet he also fought in the Russo-Turkish War of 1828 - 1829. He then remained in Odessa for two years, before travelling to St. Petersburg in 1831 where, on 16 July 1831, he died during the Cholera epidemic.
Alexander Mikaberidze, The Russian Officer Corps in the Revolutionary and Napoleonic Wars, 1792-1815, New York: Savas Beatie, 2005, pp. 218-219 Dominic Lieven, Russia against Napoleon, London: Penguin Books, 2009