Allegri, Gregorio an Italian ecclesiastic and composer of Church music, was born at Rome about 1580. He studied under Nanini and was intimate with Palestrina. He was thoroughly acquainted with harmony, and, although he did not possess a remarkable voice, was made one of the singers in the pope's chapel in 1629. He composed the famous Miserere which is performed there yearly on Wednesday and Friday of Passion-week. He died at Rome, Feb. 18, 1652.