Frederick Augustus I of Saxony

Frederick Augustus I allied Saxony with Napoleon, contributing troops to the French campaigns. Saxon forces fought in the Battle of Jena-Auerstedt (1806) and later in the invasion of Russia (1812), suffering heavy losses.

Frederick Augustus I was elevated from Elector to King of Saxony by Napoleon Bonaparte after the dissolution of the Holy Roman Empire. He became a key ally of Napoleon, joining the Confederation of the Rhine.

Frederick Augustus I remained loyal to Napoleon during the Battle of Leipzig (1813), where Saxon troops initially fought for the French but later defected to the Allies. After the battle, he was captured by the Allies and Saxony was occupied.

At the Congress of Vienna, Frederick Augustus I was forced to cede over half of Saxony's territory to Prussia, including the province of Saxony. He retained the title of King but ruled a significantly reduced state.