From the loss of the 13 American colonies to the Napoleonic Wars (1776-1815)

Having won the Seven Years' War, which gave the greatest territorial gains to the British, they ran into, in little more than a decade, a fairly unusal war where the British crown fought its own subjects: The American War of Indepedendence. Although we tend to take it for granted that the Americans,  the most powerfull nation on Earth, threw off the British yoke but it was not at all obvious when 13 American colonies declared their independence. After they had had to give up their claims in 1789, arguably partly because the French involment in the war on American side, the French Revolution broke out for devastating consequences for Europe as a whole. After 1792 the whole Europe plunged into a series of bloody military conflicts that lasted more than twenty years and can only be compared the First World War. Eventually the British came out on top, as usual; although, they had to pay an incredibly high price in capitol and human life.