On April 24, 1916 — Easter Monday — Irish republicans in Dublin and a handful of other places staged an armed rebellion against British occupation. At the time, the British Empire was the strongest power on earth; Ireland was its first and nearest colony. That the puny colony might oust the giant seemed far-fetched, and by most measures the endeavor was a failure. The leaders were executed; the British occupation continued. But not for long: the Easter Uprising is now generally understood as a crucial step in a process that led, in 1937, to full independence for most of the island. A hundred years on, some view 1916 as the beginning of the end of the British Empire.