The Anglo-Irish Treaty of 1921 led to the creation of the Irish Free State. Within sixteen years the divisive treaty link to the British Crown had been almost entirely dismantled. By the time Éamon de Valera introduced the 1937 Constitution, Ireland was effectively a republic in everything but name. In From Crown to Harp: How the Anglo-Irish Treaty Was Undone, 1921 to 1949, David McCullagh traces this remarkable, bloodless revolution.

