PLAINS, Ga. – Former President Jimmy Carter began his 93rd birthday doing what he does many Sundays, teaching a Sunday school class at his church in Plains, Georgia.
The 39th president and Nobel Peace Prize winner attends Maranatha Baptist with his wife, Rosalynn, in this farming community about 50 miles east of Columbus.
Carter, the only Georgian to be elected president, advanced from being a virtual unknown on the national stage to defeating President Gerald Ford in 1976. But several foreign policy crises, in particular the Iran hostage crisis, crushed his bid for re-election and Ronald Reagan swept into the White House.
Carter served only one term in the White House, but went on to become a prolific humanitarian after leaving office in 1981. He continues to champion causes of democracy and health internationally.
From humble roots
After high school, James Earl Carter joined the U.S. Navy, became an officer in the submarine force and worked on the nuclear propulsion system for Sea Wolf submarines.
He left the Navy in 1953 to return to his home state Georgia and worked as a peanut farmer. He ran for a seat in the Georgia State Senate in 1962 and served until 1967. In 1970, he was elected governor of Georgia.
Despite being little-known outside of Georgia when he began a presidential campaign, Carter won the 1976 Democratic nomination. In the general election, Carter defeated incumbent Republican President Gerald Ford in a close election.
Carter rebuilt his career as a humanitarian, guiding the center focused on global issues. Carter earned a Nobel Peace Prize in 2002, helped defuse nuclear tensions in the Koreas and helped avert a U.S. invasion of Haiti.
He and Rosalynn still make regular appearances at events in Atlanta and travel overseas, but maintain their primary home in Plains.
"No matter where we are in the world, we're always looking forward to getting home to Plains," Carter said.
He and his wife have thought for many years about cutting back their work at the Carter Center, which he established in 1982 to promote health care and democracy.
"We thought about this when I was 80. We thought about it again when I was 85; we thought about it again when I was 90. So this is a propitious time I think for us to carry out our long-delayed plans."
Cancer scare doesn't faze Carter
Carter announced in August 2015 that doctors had found cancer on four small spots on his brain and would immediately begin radiation treatment. He appeared upbeat speaking to reporters, saying he was "at ease with whatever comes."
"I've had a wonderful life," said Carter, who was 90 at the time. "It's in God's hands. I'll be prepared for anything that comes."
Four months months later, Carter said that he had responded well to surgery and radiation. and his body had no evidence of any cancer.
Carter received a new method of treatment called immunotherapy, which utilized his immune system to target cancerous tumors and rid his body of any evidence of cancer.
"The radiation treatment of my brain came first. The actual physical removal of a big part of my liver was effective," Carter told CNN's chief medical correspondent, Dr. Sanjay Gupta. in January 2017. "I'd say the new medication has been the key to success, perhaps."
Carter's father, brother and two sisters died of pancreatic cancer. His mother also had the disease. Carter, who had been tested for pancreatic cancer, said no cancer has been found there so far.
What the former president has, he said, is melanoma, and experts say his lifelong activities may have increased his risk for skin cancer. He lives in the South, is fair-skinned and freckled, and through Habitat for Humanity and travel, has spent a lot of time outdoors, noted Dr. Anna Pavlick, co-director of the melanoma program at NYU's Laura & Isaac Perlmutter Cancer Center.
Cancer-free, Carter continues global humanitarian work.
With a grin on his face, twinkle in his eyes and pep in his step, the 92-year-old former president sat down with CNN to explain his hope to eradicate Guinea worm disease infections in his lifetime.
"I still hope that I'll be able to survive the last case of Guinea worm," Carter said earlier this year.
For decades, the Carter Center has worked with ministries of health in nations around the world to track the number of cases of neglected tropical diseases and to help stop the spread of such diseases by providing health education and programs.
The center also has provided technical and financial assistance to national Guinea worm eradication programs to stop the actual transmission of the disease.
In 2016, the latest year for which data are available, there were only 25 reported human cases of the disease, in three countries: Chad, Ethiopia and South Sudan.
CNN contributed to this article