Michael O'Riordan (; 12 November 1917 – 18 May 2006) was the founder of the Communist Party of Ireland (3rd) and also fought with the Connolly Column in the International Brigades during the Spanish Civil War. Early life O'Riordan was born at 37 Pope's Quay, Cork city, on 11 November 1917. He was the youngest of five children. His parents came from the West Cork Gaeltacht of Ballingeary-Gougane Barra. Despite his parents being native speakers of the Irish language, it was not until O'Riordan was interned during the Second World War that he learnt Irish. As a teenager, he joined the republican youth movement, Fianna Éireann, and then the Irish Republican Army. Much of the IRA at the time was inclined towards left-wing politics. A lot of its activity at the time involved street fighting with the quasi-fascist Blueshirt movement, and O'Riordan fought the Blueshirts on the streets of Cork City in 1933–34. O'Riordan was friends with left-wing inclined republicans such as Peadar O'Donnell and Frank Ryan, and in 1934, he followed them into the Republican Congress – a short-lived socialist republican party. Spanish Civil War and Internment during the Second World War O'Riordan joined the Communist Party of Ireland in 1935 while still in the IRA and worked on the communist newspaper The Irish Workers' Voice. In 1937, following the urgings of Peadar O'Donnell, several hundred Irishmen, mostly IRA or ex-IRA men, went to fight for the Spanish Republic in the Spanish Civil War with the XVth International Brigade. They were motivated in part by enmity towards the 800 or so Blueshirts, led by Eoin O'Duffy who went to Spain to fight on the "nationalist" side in the Irish Brigade. O'Riordan accompanied a party led by Frank Ryan. In the Republic's final offensive of 25 July 1938, O'Riordan carried the flag of Catalonia across the River Ebro. On 1 August, he was severely injured by shrapnel on the Ebro front. He was repatriated to Ireland the following month, after the International Brigades were disbanded. In 1938 O'Riordan was offered an Irish Army Commission by the Irish Free State but chose instead to train IRA units in Cork. As a result of his IRA activities, during the Second World War, or the Emergency as it was known in neutral Ireland, he was interned in the Curragh internment camp from 1939 until 1943 where he was Officer Commanding of the Cork