Jimmy Carter served as president.
James Earl Carter Jr. ( born October 1 , 1924 ) is an American politician who served as the 39th President of the United States from 1977 to 1981 . The end of his presidential tenure was marked by the 1979 -- 1981 Iran hostage crisis , the 1979 energy crisis , the Three Mile Island nuclear accident , and the Soviet invasion of Afghanistan . Polls of historians and political scientists usually rank Carter as a below average president . In 2012 , he surpassed Herbert Hoover as the longest-retired president in U.S. history , and he is also the first president to mark the 40th anniversary of his inauguration .