This biography traces the life of Thomas W Sweeny who, born in Cork, came to America at the age of twelve with his mother. His life was one of war and adventure and also shows the way in which the Irish became prominently involved in events such as the Mexican War, the Indian wars, the settlement of California, the Civil War and ultimately in post-Civil War Fenian efforts toward the liberation of Ireland.

Sweeny, who rose from a Lieutenant of Volunteers to the rank of General in the US Army, was the Fenian Secretary of War and the designer of the 1866 Fenian invasion attempt on Canada. The book captures the rugged, spirited times during which a large population of Irish settled into American geographical and cultural space.