may 3, 1921 - Ireland Split
Since Ireland had officially become part of the United Kingdom in 1800, many revolts had sprung up across the country that were advocating for an independent government. This "Home Rule" idea was supported by mostly Catholics, and eventually, the pro-independence party, known as Sinn Féin, proclaimed an Irish Republic in 1919. Despite this, however, many Irish citizens living in the province of Ulster were against the idea of an independent Ireland as they thought they would be dominated by Catholic interests.
Eventually, after a small two-year war between the British forces and the Irish Republican Army, a treaty was written in December 1921. This Anglo-Irish Treaty gave Ireland a completely independent government known as the Republic of Ireland, but also allowed the province of Ulster to opt-out of the treaty should it ever want to. Ulster immediately did opt-out of the agreement and remained part of the United Kingdom, becoming known as Northern Ireland.
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History of Human Civilization
This is a rough history of human migration, advancement, and...