Born on 10 May 1918 in Ko, Ghana into a pagan family. (Poreku is his father's name.) He was baptized in 1933 and ordained to the priesthood on 11 February 1951.
Pope John XXIII appointed him the first Bishop of Wa on 16 March 1960, and he was consecrated in St Peter's Basilica, Rome on 8 May 1960 by Pope John XXIII (with Bishop Fulton J. Sheen as one of his co-consecrators). He participated in Vatican II from 1962-1965.
He was transferred to be Bishop of Tamale on 18 November 1974 and was later elevated to Archbishop when the diocese was elevate to an archdiocese on 30 May 1977. He was President of the Ghana Catholic Bishops' Conference from 1982-1988. He resigned as Archbishop in 1994.
Pope Benedict XVI created him a Cardinal at the consistory of 26 March 1994, after he was already 80 (and therefore not eligible to vote at future conclaves).