HARARE, Zimbabwe >> Amid everything else on his desk — the Iran hostage crisis, domestic economic turmoil, the Soviet invasion of Afghanistan and a grueling 1980 reelection fight — President Jimmy Carter elevated the independence of a country in southern Africa as a top agenda item.

Carter hosted then-Zimbabwean leader Robert Mugabe at the White House soon after his country achieved independence and later described Zimbabwe’s adoption of democracy as “our greatest single success.”Three decades later, Carter, who was long out of office, found the door slammed shut when he and other dignitaries sought to visit Zimbabwe on a humanitarian mission to observe reported human rights abuses after a violent disputed election in 2008. He had become a critic of Mugabe’s regime and was denied a visa.

Carter didn’t give up. From neighboring South Africa, he relied on emissaries from Zimbabwe for testimony on violence and allegations of electoral fraud. The effort reflected the former president’s long commitment to promoting democracy worldwide.

This “more than anything else cemented Carter’s legacy” as an advocate for free and fair elections across Africa, said Eldred Masunungure, a former political science lecturer at the University of Zimbabwe.

“Carter didn’t change. Zimbabwe did. Mugabe swayed from the democratic ideals that Carter held so dear,” he said. “The incident demonstrates Carter’s consistency, the steadfastness.”

Zimbabwe’s evolution toward autocracy turned out to be the kind of scenario that the Carter Center has long sought to prevent by deploying observers and developing voting standards in countries struggling to form democracies.

Established in 1982, two years after Carter lost his bid for a second term, the center has been Carter’s signature effort to promote fair elections as a vehicle for peace. It has sent observers to monitor some 125 elections in 40 countries and three tribal nations, and has been credited with helping expand democracy across the globe.

Carter’s “moral authority, the trust people put in him and the credibility of someone who had both won and lost an election” contributed to these successes, David Carroll, head of the center’s democracy program, told The Associated Press.

Carter, who died Sunday at 100, was awarded a Nobel Peace Prize in 2002 for the center’s work supporting elections, promoting human rights and helping developing countries cultivate economic, social and public health institutions.

Its elections work began in Panama, where Carter became concerned about the 1989 elections after reports of armed militia members in civilian clothes confiscating voting records during the night.

The Carter Center had just decided to expand its mission of conflict resolution and human rights to include vote monitoring, concluding that democratic elections were essential to resolving political disputes.

“In my fumbling Spanish, I stood up on a table, and I denounced the election as fraudulent,” Carter recalled in a 2015 video marking the center’s 100th election observer mission. “There was later another election, which was honest and fair, and that was the birth of real democracy in Panama.”

The center also helped rescue a peace process in Nepal, then oversaw the country’s twice-postponed elections in 2008 to elect an assembly that would be tasked with writing a constitution. Carter made several trips to the South Asian nation, holding marathon negotiations with former rebels and top politicians to keep the peace process on track.

“There was deadlock in the country. Political parties were not sitting together, and there was no way out on how the process will move on,” said Bhojraj Pokharel, Nepal’s chief election commissioner in 2008, who later worked with Carter in Congo and Myanmar.

On Nepal’s election day, Carter traveled to dozens of polling stations talking to voters. Polling was peaceful despite earlier fears of violence.

“His presence itself was a message to the Nepalese population and voters about the integrity of the election,” Pokharel said.

The Carter Center often works in countries with little or no experience in representative government and where trust has all but evaporated because of violence.

After Bolivia held elections in 2019 that the Organization of American States said were marred by fraud, the country’s electoral tribunal invited the Carter Center to observe elections the following year. The center deployed a team to Bolivia and later commended the country for elections it called impartial and transparent.