The Partition of Ireland occurred in 1921, dividing the island into two distinct political entities: Northern Ireland and the Irish Free State. This division was largely based on religious and political differences, with Northern Ireland having a majority of Protestants who identified as British, while the Irish Free State was predominantly Catholic and sought independence from British rule. The partition was formalized with the Government of Ireland Act 1920, which created a devolved government for Northern Ireland. This division led to significant social and political tensions, contributing to decades of conflict known as The Troubles, which lasted from the late 1960s until the 1998 Good Friday Agreement.