Partition of Ireland

The partition of Ireland (Irish: críochdheighilt na hÉireann) was the division of the island of Ireland into two distinct jurisdictions, Northern Ireland and Southern Ireland. It took place on 3 May 1921 under the Government of Ireland Act 1920. Today the former is still known as Northern Ireland and forms part of the United Kingdom while the latter is now a sovereign state also named Ireland, formally known as the Republic of Ireland.

The Act of 1920 was intended to create two self-governing territories within Ireland, with both remaining within the United Kingdom. It also contained provisions for co-operation between the two territories and for the eventual reunification of Ireland. However, in 1922, following the War of Independence and the Anglo-Irish Treaty, the southern part became independent as the Irish Free State, while Northern Ireland exercised its option to remain in the United Kingdom.

Since partition, a key aspiration of Irish nationalists has been to bring about a reunited Ireland, with the whole island forming one independent state. This goal conflicts with that of the unionists in Northern Ireland, who want the region to remain part of the United Kingdom. The British and Irish government agreed, under the 1998 Belfast Agreement, that the status of Northern Ireland will not change without the consent of a majority of its population. In its white paper on Brexit the United Kingdom government reiterated its commitment to the Belfast Agreement. With regard to Northern Ireland's status, it said that the UK Government's "clearly-stated preference is to retain Northern Ireland’s current constitutional position: as part of the UK, but with strong links to Ireland".

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