 His father, James Clark Sr. (1885–1955), was a judge of the Fifth Circuit Court whose family's roots in Howard County, Maryland traced back to 1797.His mother was Alda Tyson Hopkins, whose family line traced back to the Ellicott and Hopkins families (she was a relative of the philanthropist Johns Hopkins).James and Alda Hopkins Clark lived at Keewaydin, a farm located near Ellicott City, Maryland, and also owned a nearby farm known as Elioak Farm.