Stephens Most likely a surname adopted by the descendants of the Cambro-Norman invaders in Connacht: FitzStephens. In 1890 Stephens was principally found in Mayo, and the estimated number of bearers was 1,610. In the United States it is the 165th most numerous surname with an estimated 156,750 bearers. In England and Wales in 1996 it was the 246th most numerous surname.