The twin battles of Jena and Auerstedt were fought on 14 October 1806 on the plateau west of the river Saale in today's Germany, between the forces of Napoleon I of France and Frederick William III of Prussia. The defeat suffered by the Prussian Army subjugated the Kingdom of Prussia to the French Empire until the Sixth Coalition was formed in 1813.

Napoleon Bonaparte, later known by his regnal name Napoleon I, was a French emperor and military commander who rose to prominence during the French Revolution and led successful campaigns during the Revolutionary Wars. He was the leader of the French Republic as First Consul from 1799 to 1804, then of the French Empire as Emperor of the French from 1804 until 1814, and briefly again in 1815. His political and cultural legacy endures as a celebrated and controversial leader. He is considered one of the greatest military commanders in history and his wars and campaigns are still studied at military schools worldwide. However, historians still debate the degree to which he was responsible for the Napoleonic Wars, in which between three and six million people died. Napoleon brought modernizing reforms to France and Western Europe and stimulating the development of nation states. He also sold the Louisiana Territory to the United States in 1803, doubling the latter's size. However, his mixed record on civil rights and exploitation of conquered territories adversely affect his reputation.