Original sentence: A majority of the population are unionist and wish to remain part of the United Kingdom, but a significant minority, known as nationalists, want to see a united Ireland.Ireland was partitioned by the British government in 1921 under the terms of the Government of Ireland Act 1920 between Northern Ireland and Southern Ireland (which became the Irish Free State in 1922).The conflict between these two sets of identities, and alleged discrimination against nationalists under the Northern Ireland government (1920–72), gave rise to a long-running conflict known as The Troubles.When the latter achieved independence, the six counties of Northern Ireland — under the procedures laid out in the Anglo-Irish Treaty, 1921 — declined to join, and so remained as part of the United Kingdom
Edited sentence: A majority (52%) of the population are unionist and wish to remain part of the United Kingdom, but a significant minority, known as nationalists, want to see a united Ireland.Ireland was forcibly partitioned by the British in 1921 under the terms of the Government of Ireland Act 1920 between Northern Ireland and Southern Ireland (which became the Irish Free State in 1922).The conflict between these two sets of identities, and long-running discrimination against nationalists under the Northern Ireland government (1920–72), gave rise to a long-running conflict known as The Troubles.When the latter achieved independence, the British government— under the procedures laid out in the Anglo-Irish Treaty, 1921 — refused to grant independence to the whole island and so the northern area was forcibly retained as part of the United Kingdom in spite of the wishes of the vast majority of the people on the island