Quoting from this Economist post;
“Waterloo not only brought to an end the extraordinary career of Napoleon Bonaparte, whose ambitions had led directly to the deaths of up to 6m people. It also redrew the map of Europe and was the climax of what has become known as the second Hundred Years War, a bitter commercial and colonial rivalry between Britain and France that had begun during the reign of Louis XIV.
Through its dogged resistance to France’s hegemonic ambitions in the preceding 20 years, Britain helped create the conditions for the security system known as the Concert of Europe, established in 1815. The peace dividend Britain enjoyed for the next 40 years allowed it to emerge as the dominant global power of the 19th century.”