This track was used prominently in the 1968 film If . . .
It is from the Missa Luba, a setting of the Latin Mass in styles traditional to the Democratic Republic of Congo. It was composed by Father Guido Haazen, a Franciscan friar from Belgium, and recorded in 1958 by Les Troubadours du Roi Baudouin (King Baudouin’s Troubadours), a choir of adults and children from the Congolese town of Kamina in Katanga Province.
Released as a single, it reached No 28 in the UK in 1969.