The French Revolution had a significant impact throughout Europe, which only increased with the arrest of King Louis XVI of France in 1792 and his execution (January 1793). The first attempt to crush the French Republic came in 1792; the war ended when Napoleon Bonaparte forced the First Coalition (Austria, Sardinia, Naples, Prussia, Spain, and Great Britain) to accept his terms in the Treaty of Campo Formio. On May 18, 1804, Napoleon Bonaparte declared France an Empire and crowned himself Emperor at Notre-Dame on December 2, 1804. The British Army, unlike its many coalition partners, remained the only anti-French power involved throughout the entire period of the Napoleonic Wars. Great Britain gave long-term support to the Spanish rebellion in the Peninsular War of 1808-1814. Anglo-Portuguese forces succeeded in harassing French troops for several years. By 1815, the British Army would play a central role in the final defeat of Napoleon at Waterloo (18 June 1815) and the Second Treaty of Paris.