Giovanni Battista Costanzo (died 1617) was a Roman Catholic prelate who served as Archbishop of Cosenza (1591–1617).[1][2][3]
On 5 April 1591, Giovanni Battista Costanzo was appointed during the papacy of Pope Gregory XIV as Archbishop of Cosenza.[1] On 21 April 1591, he was consecrated bishop by Giulio Antonio Santorio, Cardinal-Priest of San Bartolomeo all'Isola, with Leonard Abel, Titular Bishop of Sidon and Giovanni Battista Santorio, Bishop of Tricarico serving as co-consecrators.[1] He served as Archbishop of Cosenza until his death in 1617.[1] While bishop, he was the principal consecrator of Francesco Monaco, Bishop of Martirano (1592); and Decio Caracciolo Rosso, Archbishop of Bari (1606).[1]