The Royal Irish Constabulary (RIC) was the main police force in Ireland under British rule in the late 19th and early 20th centuries.
Formerly the Irish Constabulary, the RIC was granted its 'Royal' prefix following the Fenian Rising of 1867. The RIC carried out normal policing duties but also had a paramilitary role, carrying out duties that elsewhere might have been performed by troops; it was organized in a quasi-military fashion, being based in police barracks, and its members wore a military-style dark green uniform and were armed with rifles. It was not a sectarian force: most members were Catholic, and when the RIC took over the duties of the disbanded Belfast and Londonderry police forces, its members were received with suspicion by the local Protestant populations.
However, the force became increasingly unpopular for its role in enforcing rural evictions and other policies for which there were objections by the nationalist population, and when the Irish War of Independence broke out - with the shooting of two policemen in 1919 - the force was in the front line. Policemen and police families were subjected to a boycott enforced by the IRA, several hundred isolated barracks were burned, and more than 400 police were killed.
In the wake of this disaster, many hundreds of policemen resigned, and the RIC had to be reinforced by recruiting British ex-servicemen for reserve units: the notorious Black and Tans ('Tans') and the Auxiliary Division ('Auxies'). At the conclusion of the war and the division of Ireland into the Irish Free State and Northern Ireland, the RIC was dissolved and replaced by two forces: the Garda Siochana in the Free State (which also absorbed the hitherto independent Dublin Metropolitan Police), and the Royal Ulster Constabulary in Northern Ireland.