James Hamilton Couper wrote and signed his last will and testament on 12 September 1863. The will was probated 6 August 1866, he died 3 June 1866, without ever having changed his will.

J.H. Couper owned the plantations on St. Simons Island known as Hamilton, Cannons Point, and Couper's Point. He also owned Altama located in the northern part of Brunswick, which is now located off of Hwy. 99, west of Hwy 17. Other tracts of land owned by him were Long Island (now known as Sea Island), Magnolia in Buffalo Swamp, land near Scranton, and a tract of land in Cowpen Swamp.

To his wife, Caroline Georgia Couper, he leaves, among other property, the house servants Abraham, Abby, Balally?, and Ellen. He also left 20 of his "Negro slaves" for her to choose, "reference being mainly had to connections with her own gang."