|IV Corps (Grande Armée)|
|Country||First French Empire|
|Size||Three or four infantry divisions, cavalry, artillery|
François Joseph Lefebvre
Horace François Sébastiani
Eugène de Beauharnais
Henri Gatien Bertrand
Étienne Maurice Gérard
IV Corps formed part of the extended center of the French line at the Battle of Austerlitz in December 1805. On the 2nd, Napoleon ordered Soult to attack the Pratzen Heights, from which the Allies had been attacking the French right wing. Repeated attacks from the Russians under General Kutusov almost collapsed IV Corps' line, but aid from Bernadotte's I Corps allowed the French to maintain their control of the Heights. The survivors then moved south and enveloped Buxhowden's column, sending the Allies into a retreat.
IV Corps formed the right wing of the French line at the Battle of Jena in October 1806. At Eylau in February 1807, IV Corps was beaten back by the Russian army under Generals Tutchkov and Dokhturov.
When Austrian went to war in 1809 many French units nominally belonged to IV Corps were not concentrated yet. It were detached under command Marshals Bessières and Massena and took part in battles of Landshut, Neumarkt and Ebelsberg. Later reorganised IV Corps under Massena fought in Battles of Aspern-Esling and Wagram.
The IV Corps consisted mainly of the Army of the Kingdom of Italy (Napoleonic) during the 1812 invasion of Russia. It was commanded by Napoleon's stepson Eugène de Beauharnais. The IV Corps most notably participated in the Battle of Borodino, where it formed the left wing of the French line. Later it also fought hard at Malojaroslavec and Viazma. The IV Corps suffered heavy casualties during winter retreat.