Partition of Ireland
The partition of Ireland () divided 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 and sometimes called the Republic of Ireland.
1973 Northern Ireland border poll
The Northern Ireland border poll was a referendum held in Northern Ireland on 8 March 1973 on whether Northern Ireland should remain part of the United Kingdom or join with the Republic of Ireland to form a united Ireland. It was the first time that a major referendum had been held in any region of the United Kingdom. The referendum was boycotted by nationalists and resulted in a conclusive victory for remaining in the UK. On a voter turnout of 58.7 percent, 98.9 percent voted to remain in the UK.