Carter's first task back home in Georgia was writing an autobiography that charted the achievements and disappointments of an unfulfilled political career while he searched for a more permanent role.
Then, late one night, lying in bed after a few hours sleep, he had a revelation -- he would not just build a presidential library, but would set himself up as a freelance global mediator, statesman and global health advocate who would work across political and humanitarian divides.
"This was the birth of the Carter Center," the former president wrote.
The Carter Center's work would eventually recast the roles and expectations of ex-presidents, and his move into global relief and humanitarian work after the White House has been emulated by successors like Bill Clinton and George W. Bush.
Over the next three-and-a-half decades, Carter would venture into global hotspots, negotiate with rogue leaders like North Korea's dictators Kim Il Sung and Kim Jong Il and launch a broad, global humanitarian mission.
He fought to eradicate diseases afflicting hundreds of millions of people in tropical Africa, including river blindness, malaria, and trachoma. He plunged into civil wars and conflicts from Nepal to Ethiopia, the Balkans and Sudan and across the Middle East.
He is credited with helping to peacefully restore order in Haiti in 1994 after the overthrow of President Jean-Bertrand Aristide, averting the need for American military action at a moment when U.S. bombers were already in the air.
The Carter Center has monitored elections in 100 nations, and Carter and his beloved wife,
Rosalynn, have also devoted a week of work every year to the charity Habitat for Humanity, which builds and renovates homes for poor families.