Currently, the world’s longest-serving leader is Equatorial Guinea’s President Teodoro Obiang Nguema, with 43 years under his belt since he toppled his uncle in 1979.
Paul Biya, 86, took over the president’s office in 1982 after a seven-year stint as prime minister.
Cambodia’s Prime Minister Hun Sen began his fifth term in 2018, cementing his position among the world’s longest rulers. The 67-year-old has been in power for 38 years.
Longtime President Yoweri Museveni took power by force in 1986 and declared himself president. He’s been re-elected several times since then.
Iran’s second Supreme Leader Ayatollah Ali Khamenei took the position in 1989 and has since been in power.