The Black and Tans were constables recruited into the Royal Irish Constabulary (RIC) as reinforcements during the Irish War of Independence. Recruitment began in Great Britain in January 1920 and about 10,000 men enlisted during the conflict. The majority were unemployed former British soldiers from England who had fought in the First World War. Some sources count Irish recruits to the RIC from 1920 as 'Black and Tans'.

The Royal Irish Constabulary was the police force in Ireland from 1822 until 1922, when all of the country was part of the United Kingdom. A separate civic police force, the unarmed Dublin Metropolitan Police (DMP), patrolled the capital and parts of County Wicklow, while the cities of Derry and Belfast, originally with their own police forces, later had special divisions within the RIC. For most of its history, the ethnic and religious makeup of the RIC broadly matched that of the Irish population, although Anglo-Irish Protestants were overrepresented among its senior officers.