His father, also Cathal O'Shannon, was a republican from Co Derry. He had joined the Irish Republican Brotherhood and was imprisoned following the 1916 Rising, although he had taken no part in it, because of the confusion that attended the preparations of the Irish Volunteers. He had also been an official of the Irish Transport and General Workers' Union, first in Belfast and then in Dublin. He was a Labour TD and in later life was a member of the Labour Court.

Young Cathal was born in Marino, Dublin, in 1928. He went to school in Marino and then to Colaiste Mhuire. From there he joined Britain's Royal Air Force. He and a school friend, Fred O'Donovan, later chairman of the RTE Authority and of the Concert Hall, lied about their ages and were recruited in Belfast.

They were first sent to Long Kesh. Cathal was then sent to the Far East, having trained as a gunner, but missed taking part in the war, following the Japanese surrender after Hiroshima. He spent two years in Burma and Malaya. His first dabblings in journalism were for an RAF paper.

He became one of the most colourful figures in Irish journalism, although he abandoned it for 15 years to work in public relations for Alcan in Co Limerick.

Last year he underwent surgery for cancer but he still looks at least 15 years younger than his age (73 this year). He lives with his wife, Patsy, on Anglesea Road, Dublin.