Origins

• The Easter Uprising of 1916 was intended to establish an independent republic in Ireland. The British quickly crushed the revolt and executed its leaders, but unrest remained. Remnants of the revolt reorganized under Michael Collins and became the military branch of Sinn Fein, a political party dedicated to Irish independence. An extensive guerilla campaign against British occupation followed, as the IRA conducted bombings, military raids and similar operations. In 1922, their efforts succeeded in securing Irish independence, though it came at a heavy price.
  
  

Irish Free State

• The treaty which created an Irish Free State in 1922 left six northern Irish counties under control of the British. The act also created deep rifts in the IRA, with more radical elements demanding complete independence and more conciliatory elements supporting the treaty. A civil war began in June of 1922, and lasted for nine months. In the end, the anti-treaty branch of the IRA was defeated, though they inflicted hundreds of casualties in the process.
  
  

The Border Campaign

• IRA activity remained sporadic for many years, but it flared up again in the 1950s with an energized campaign to reclaim Northern Ireland from the British. Raids on British army bases netted weaponry, and IRA leaders such as Sean Cronin planned attacks in Northern Ireland designed to disrupt infrastructure and the British Army's ability to function. The campaign went on for several years, finally ending in 1961 after garnering little popular enthusiasm for its goals.
  
  

Split

• The Civil Rights Movement of the 1960s had a profound effect on Northern Ireland, as irate pro-nationalists campaigned for increased freedoms. They met fierce resistance from pro-British police and groups such as the RUC (Royal Ulster Constabulary). The IRA split over how to respond to the unrest, with the "official" branch disavowing violence and the "provisional" branch advocating terrorist activities. The provisional IRA then undertook a series of bloody attacks, both in Northern Ireland and Great Britain. After a Birmingham pub was bombed in 1974, the British outlawed the IRA in their territory, which didn't stop the provisional branch from launching continued bombings and assassination attempts for decades to come.
  
  

Cease-Fire and Peace

• In 1994, the IRA declared a cease-fire in its guerilla campaign. Talks began with the British government, periodically broken off by renewed attacks, but continuing in hopes of forging a lasting peace. In 1999, a new accord provided for closer ties between Northern Ireland and the Irish Republic. In 2005, the IRA declared an end to its attacks, and reports since indicate that they have made good on their promise to disarm.