Chun Doo-hwan ( Korean pronunciation : ( tɕʌnduhwan ) born 18 January 1931 ) is a ROK Army general who served as the leader of South Korea from 1979 to 1988 , ruling as an unelected military strongman from December 1979 to September 1980 , and the fifth President of South Korea from 1980 to 1988 .
Chun Doo-hwan ( born 18 January 1931 ) was a Korean military officer and the President of South Korea from 1980 to 1988 .