Hiram Rigg was born 1841 in Michigan. He died 27 July 1864 and was buried in Andersonville National Cemetery, Andersonville, Georgia.
Hiram and his brother Truman enlisted in the Civil War on September 19, 1864. Both, Hiram and Truman were Privates in Company H, 21st Infantry Regiment of Ohio. Hiram was captured at Chickamauga, Georgia and became a POW. He died a prisoner of war at the Andersonville Prison. He is buried in the Andersonville National Cemetery in Section J Site 4061.