Sadao Yamahana (山花 貞夫, Yamahana Sadao; 26 February 1936 – 14 July 1999) was a Japanese politician who served as chairman of the Japan Socialist Party from January 1993 to September 1993. Yamahana led his party into coalition with other opposition parties to form the first non-LDP cabinet since 1955, led by Prime Minister Morihiro Hosokawa. Yamahana served as Minister in charge of political reform in the same cabinet. Yamahana later left the Socialists and became a founding member of the Democratic Party.
Source: “Sadao Yamahana”, English Wikipedia (CC BY-SA 4.0), excerpt