 He was the son of John Lawrence Ireland (1796–1879) and Mary (née Floyd) Ireland (1798–1887), the sister of U.S. Representative John Gelston Floyd.John's younger brother was Nicoll Floyd Ireland.His paternal grandparents were John Ireland and Judith (née Lawrence) Ireland (a daughter of New York State Senator Jonathan Lawrence and the former Ruth Riker, a member of the Riker family, for whom Rikers Island is named).