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.
Italian Renaissance painting
Raphael, who moved to Florence in 1504 and to Rome in 1508, unashamedly drew on the skills of the renowned painters whose lifespans encompassed his. In his works the individual qualities of numerous different painters are drawn together. The rounded forms and luminous colours of Perugino, the lifelike portraiture of Ghirlandaio, the realism and lighting of Leonardo, and the powerful draughtsmanship of Michelangelo became unified in the paintings of Raphael. In his short life he executed a number of large altarpieces, an impressive Classical fresco of the sea nymph, Galatea, outstanding portraits with two popes and a famous writer among them, and, while Michelangelo was painting the Sistine Chapel ceiling, a series of wall frescoes in the Vatican chambers nearby, of which "the School of Athens" (1509-11) in the Stanza della Segnaturais is uniquely significant.