How did America end up in the Napoleonic Wars?

Answer 1

Britain was short on manpower for its warships after many years of warfare with France. British sea captains found that they could stop American merchant ships at sea and force American merchant sailors into service as British sailors. Some Americans were killed because of refusal to serve the British and others were war casualties.

America protested to the King of England to stop this unfair and illegal practice but the impressment of Americans into the Royal Navy did not stop.

In the belief that the British were very much tied down in a war in Europe, and therefore could be forced to negotiate, America declared war on Britain. America was thus on the side of Napoleon. Britain and America fought a series of mostly inconclusive series of battles that included the burning of Washington. Early in 1814, Napoleon's army was crushed and Britain was able to throw large numbers of experienced combat troops into America. Fortunately, cooler heads prevailed and the two sides agreed to end the war.