Garda Síochána
The first Commissioner, Michael Staines, who was a Pro-Treaty member of , held office for only eight months. It was his successors, Eoin O'Duffy and Éamon Broy, who played a central role in the development of the force. O’Duffy was Commissioner in the early years of the force when to many people’s surprise the ability of the force to succeed despite being unarmed was established. O'Duffy later became a short-lived political leader of the quasi-fascist Blueshirts before heading to Spain to fight alongside Francisco Franco's Nationalists in the Spanish Civil War. Broy had greatly helped the Irish Republican Army (IRA) during the Anglo-Irish War, while serving with the Dublin Metropolitan Police (DMP). Broy's fame grew in the 1990s when he featured in the movie Michael Collins, in which it was misleadingly suggested that he had been murdered by the British during the War of Independence, when in reality he lived for decades and headed the Garda Síochána from 1933 to 1938. Broy was followed by Commissioners Michael Kinnane (1938–52) and Daniel Costigan (1952–65).  The first Commissioner to rise from the rank of ordinary Garda was William P. Quinn, who was appointed in February 1965.