Career
She has written extensively on the Irish revolution of 1916-1923. Among her books are The Tom Barry Story (1982)- later updated and revised as Tom Barry, Ireland Republican Army Freedom Fighter in 2003 - The Day Michael Collins was Shot (1998), Michael Collins and the Women in his Life (1998), Liam Lynch the Real Chief (2005) and Michael Collins and the Women who Spied for Ireland (2006). She was involved in a dispute with historian Peter Hart over questions he raised in his book The Ireland Republican Army and its Enemies over the Kilmichael Ambush in 1920 and the Dunmanway killings in 1922.
Ryan argued that the Auxiliaries were killed after a "false surrender" and that those killed in 1922 were informers to British forces.
