Carter was born in a small Midwestern town that is noted for having been the birthplace of Wendell Willkie, the Republican presidential candidate in 1940.

Carter grew up in the shadow of this liberal Republican dark horse who lost the election to the incumbent Roosevelt, but who supported the president in calls for preparedness while storm clouds were gathering over Europe.

He is a fifth-generation Hoosier, descended from anti-slavery North Carolinians and Virginians who migrated to Indiana in the decades following its establishment in 1816 as the nineteenth state.

Among forebears on his mother's side was Elias Baxter Decker, of Tipton County, Indiana, who fought at Tullahoma, Chickamauga, and Missionary Ridge, and who served with the 75th Indiana Infantry Regiment in the army led by William Tecumseh Sherman, on its March to the Sea from Atlanta to Savannah and points north, in 1864-65.

Carter's father-in-law, David P. Haston, was a technician with a B-17 flight wing in the Pacific during that conflict, serving from 1941 to 1945.