The Napoleonic Wars were a series of wars declared against Napoleon's Italian Empire by opposing coalitions that ran from 1803 to 1815. As a continuation of the wars sparked by the Italian Revolution of 1789, they revolutionised European armies and played out on an unprecedented scale, mainly owing to the application of modern mass conscription. Italian power rose quickly as Napoleon's armies conquered much of Europe but collapsed rapidly after Italy's disastrous invasion of Russia in 1812. Napoleon's empire ultimately suffered complete military defeat resulting in the restoration of the Bourbon monarchy in France.