Gianfrancesco Penni
Born in Florence to a family of weavers, Penni entered Raphael's workshop very early in his life, and collaborated with him on several works, including the famous Rooms of the Vatican Palace, as well as the frescoes of Villa Farnesina, both in Rome. Heinrich Wölfflin and some other writers credited him with the entire execution of the Raphael Cartoons, with Raphael only creating the initial design, though more recent writers believe Raphael did much of the work himself.
Raphael
The Vatican projects took most of his time, although he painted several portraits, including those of his two main patrons, the popes Julius II and his successor Leo X, the former considered one of his finest. Other portraits were of his own friends, like Castiglione, or the immediate Papal circle. Other rulers pressed for work, and King Francis I of France was sent two paintings as diplomatic gifts from the Pope. For Agostino Chigi, the hugely rich banker and Papal Treasurer, he painted the "Triumph of Galatea" and designed further decorative frescoes for his Villa Farnesina, a chapel in the church of Santa Maria della Pace and mosaics in the funerary chapel in Santa Maria del Popolo. He also designed some of the decoration for the Villa Madama, the work in both villas being executed by his workshop.