Giovanni Pierluigi da Palestrina

Introduction at wikipedia: Giovanni Pierluigi da Palestrina (3 February 1525 or 2 February 1526 – 2 February 1594) was an Italian Renaissance composer of sacred music and the best-known 16th-century representative of the Roman School of musical composition. He had a lasting influence on the development of church music, and his work has often been seen as the culmination of Renaissance polyphony.

Introduction at Catholic Encyclopedia.