Frank Ryan (Irish: Proinsias Ó Riain; 11 September 1902 – 10 June 1944) was an Irish politician, journalist, intelligence agent and paramilitary activist.
He first came to prominence as an Irish republican activist at University College Dublin and fought for the Irish Republican Army during the Irish Civil War.
Ryan fell under the influence of Peadar O'Donnell, an advocate of Marxist-Leninism within Irish republicanism, which resulted in him breaking with the IRA and becoming involved with founding a new political organisation, the Republican Congress, and editing its associated newspaper: An Phoblacht.
Along with others, Ryan participated in the Spanish Civil War on the Popular Front side, fighting for the Comintern-organised International Brigades (retroactively known as the Connolly Column).
After being captured by pro-Nationalist Italians, he was sentenced to death but later granted an 'escape' by Franco personally.
He was released into the hands of the Abwehr (military intelligence of Germany) and transported to Berlin.
Ryan spent the rest of World War II until his 1944 death working as an IRA–Abwehr go-between on operations such as Dove, Whale and Sea Eagle.