On January 1, 1937 the barrio of Buenavista, by virtue of Executive Order No. 65 issued by Commonwealth President Manuel L. Quezon, became the Municipality of Buenavista through the efforts of assemblyman Apolonio D. Curato and Governor Jose R. Rosales, commissioner of Mindanao and Sulu Teofisto Guingona Sr., and secretary of Interior, Elpidio Quirino, with a set of appointed officials to serve for a period of one year.
Guingona was a delegate to the 1971 Constitutional Convention and when martial law was declared in 1972 by President Ferdinand Marcos, he resisted the abuses of the regime, serving as a human rights lawyer.