Composer, born in Palestrina, Italy. At Rome he learned composition and organ playing, and became organist and maestro di canto at the cathedral of St Agapit, Palestrina (1544). In 1551 he became master of the Julian choir at St Peter's, the first of several appointments in Rome. The most distinguished composer of the Renaissance, he composed over 100 Masses, motets, hymns, and other church pieces, and in 1577 began a revision of the Gradual (which he later abandoned).