The primary cause of the Napoleonic Wars, which spanned from 1803 to 1815, was the expansionist ambitions of Napoleon Bonaparte and the struggle for dominance within Europe. Following the French Revolution, Napoleon sought to spread revolutionary ideals and assert French hegemony across Europe. This led to a series of conflicts as various coalitions of European powers, including Britain, Austria, and Russia, joined forces to contain and resist his influence. The wars fundamentally altered the political landscape of Europe, leading to the eventual rise of nationalism and significant changes in territorial boundaries.