The 1st Swiss Regiment (French: 1ère Régiment Suisse) was a Swiss mercenary line infantry regiment in the French Imperial Army during the Napoleonic Wars. During the expansion of the Imperial Army in 1803, Napoleon decreed the formation of four Swiss mercenary regiments, one of these later becoming the famed 1st Swiss. After a short time serving in Southern Italy, notably serving at the Battle of Maide, the 1st Swiss were sent to Poland for the impending Invasion of Russia. During the invasion, the regiment remained in the reserve, but served with honour, notably at the Battles of Polotsk and later the crossing of the Berezina. After retreating from Russia, elements of the regiment served during the minor campaigns until May 1814. The regiment was then reformed under the Bourbon restored m