Franco was the pride of what was then (and would be again) the Democratic Republic of Congo, for a brief spell known as Zaire.  He went from singing rumba and bolero tunes to developing a funk-influenced sound that lit up most of the African continent.  From the Bandcamp site:

“This compilation brings together an original selection of 16 tracks from the first three years of Les Editions Populaires. They are a showcase of the sound Franco had envisioned for his band. The focus was less on cha-cha-cha and Spanish lyrics, but on lingering rumba and bolero ballads in Lingala, tradition-rooted songs in Kikongo, Kimongo and even Yoruba, collaborations with Ngoma artists Camille Feruzi and Manuel d’Oliveira and not to forget solid pastiches of American funk, which were showing that the OK Jazz musicians had an open-minded view on music and were capable of excelling in many genres. Mama Na Ngai indeed!“