Callan, County Kilkenny
He was born in 1812 in Puebla de los Ángeles, in the state of Puebla, New Spain (colonial Mexico). His father was of Irish descent; his lineage traced back to Callan, County Kilkenny, from where Comonfort's grandfather, Joseph Comerford, immigrated to Mexico (the surname would be later changed to "Comonfort"). He participated in the Mexican–American War.