Results for D. João IV (not all results may be relevant):
John IV (D. João IV) was the king of Portugal and the Algarves from 1640 to his death.
John IV was a patron of music and the arts, and a considerably sophisticated writer on music; in addition to this, he was a composer. During his reign he collected one of the largest libraries in the world, but it was destroyed in the Lisbon earthquake of 1755. Among his writings is a defense of Palestrina, and a Defense of Modern Music (Lisbon, 1649).