Károly Bartha started his sports career as a football player and an athlete, but in 1922 his swimming talent was discovered and he became a swimmer with Nemzeti SC. He was primarily successful in backstroke. Bartha won the national championship title in the 100 metre backstroke three times, adding five national titles in relays. At the 1924 Paris Olympics, he finished third in the 100 back and was second at the 1926 European Championships. Bartha was a promising talent, but in 1927 he ended his sports career due to financial problems. He first settled in Italy where he worked as an artist and then emigrated to the United States in 1962, where he owned a Hungarian restaurant called “Csárdás” in Boston.