Short answers, pulled from the story.
Giovanni Pierluigi da Palestrina arrived in the world between the 3rd of February 1525 and the 2nd of February 1526 within the town of Palestrina. This small community sat inside the Papal States during his childhood years.
Pope Paul IV ordered all papal choristers to be clerical men rather than laymen which prevented Giovanni Pierluigi da Palestrina from continuing his service. He had married early in life and fathered four children so he could not serve as a layman under these strict rules.
Palestrina left behind hundreds of compositions including over 105 masses and more than 300 motets. His output included 68 offertories and at least 140 madrigals alongside numerous hymns.
The Council of Trent never officially banned any church music or made an official statement on the subject. Historical records show that the Missa Papae Marcelli existed possibly ten years before those discussions began yet stories originated from unofficial points-of-view shared by attendees not privy to deliberations.
Johann Joseph Fux published Gradus ad Parnassum in 1725 using Giovanni Pierluigi da Palestrina as a model for counterpoint training. The method became the main basis of contrapuntal training throughout the 19th century with Bach arranging two of Palestrina's masses for performance and endorsing Fux's manual.