William Henry Elder was an American prelate of the Catholic Church. He served as bishop of the Diocese of Natchez in Mississippi from 1857 to 1880 and as archbishop of the Archdiocese of Cincinnati in Ohio between 1883 and his death.

The Diocese of Jackson is a Latin Church diocese in Mississippi in the United States. Its ecclesiastical jurisdiction includes the northern and central parts of the state, an area of 97,458 square kilometers (37,629 sq mi). It is the largest diocese, by area, east of the Mississippi River.