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How did the Government of Ireland Act of 1920 divide Ireland?
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the Troubles
Local people walking past a British soldier on guard in Northern Ireland, August 1969.
The Government of Ireland Act of 1920 divided Ireland into two separate, self-governing units, each with devolved powers similar to Home Rule.123
- Northern Ireland: This unit was formed from six of Ulsterās nine countiesāAntrim, Armagh, Down, Fermanagh, Londonderry (Derry), and Tyrone. This specific configuration was chosen because it provided the largest area in which Ulster Unionists could maintain a permanent political majority.123
- Southern Ireland: This unit comprised the remaining 26 counties of the island, which included the three Ulster counties with significant Catholic nationalist majorities: Donegal, Cavan, and Monaghan.123
While the act intended to establish self-government for both regions, it was rejected by Sinn FĆ©in and never effectively implemented in the south. Following the Anglo-Irish Treaty of 1921, the southern counties became the Irish Free State, while Northern Ireland exercised its right to opt out of that arrangement, remaining part of the United Kingdom.123