From 6 January 1920, recruiting to the Royal Irish Constabulary (RIC) was extended outside of Ireland to candidates with military experience to supplement the native Irish force, then depleted by massive resignations, suffering IRA attacks, and widespread social exclusions. This new force was called the RIC Special Reserve. By July 1921 a total of 7,683 candidates recruited in Britain (381 Irish-born) had arrived in Ireland. From 3 September 1920 a second and separate group of 2,189 'Temporary Constables' (312 Irish-born) were recruited and attached to the newly-opened headquarters of the motorised division of the RIC at Gormanston Camp in Co. Meath. A third group known as the Veterans & Drivers Division attached to Gormanston Camp comprising of 1,069 (190 Irish-born) were recruited. Due to huge volume of recruits being immediately required and arriving in Ireland at such short notice, there was a shortage of complete regular 'rifle-green' RIC uniforms being available, they were fitted initially with ill-fitting khaki trousers and green tunics and vice-versa and collectively by March 1920 gained the title 'Black & Tans.' Even though the uniform situation was sorted by December 1920, the title 'Black & Tans' would remain long after into history. In this book Jim Herlihy lists alphabetically, every individual member of these three distinct groups who was liable to be called a 'Black and Tan.' The lists include the RIC registered number, surname, forename, birth year, native country & county, religion, the recruiting office where they enlisted, whether they had served as a soldier or as a sailor, previous occupation and whether they, resigned (with the given excuses), were discharged or dismissed, pensioned or disbanded, were killed or died in the service.The book also includes a chapter on tracing and identifying 'Black and Tan' ancestors in the RIC Nominal Roll of 1 January 1921 with several sets of appendices.

Jim Herlihy , (Author), Dublin , (Ireland) - Jim Herlihy, a retired member of the Garda Síochána and a co-founder of the Garda Síochána Historical Society, has worked on these sources for many years. His many publications include The Royal Irish Constabulary: a short history and genealogical guide (2016) and Royal Irish Constabulary officers: a biographical dictionary and genealogical guide, 1816–1922 (2005).