Filippo Salviati was born in Florence in 1582. According to some sources he was a disciple of Galileo in Padua. He was certainly a great friend of his.
A descendant of the powerful Salviati house and allied through marriage with the Medici family, Filippo lost his mother at birth and his father when he was twelve. He was raised by his uncle Antonio who trained him to manage the banks which had been the source of the family's wealth. But when he came of age Filippo preferred to give up his riches in favor of a modest income that would allow him to lead the life of a scholar rather than that of a businessman.
Galileo spent long periods at Villa 'Le Selve', the Salviati family residence near Lastra a Signa, conversing with his friend and making his observations in the tranquillity of the Florentine countryside. His first and third letters on sunspots are dated 1612 and were written right at Villa 'Le Selve'. He dedicated his Istoria e dimostrazioni intorno alle macchie solari [History and Demonstrations concerning Sunspots] (Rome, 1613) to Salviati, and in 1612, after Filippo had become a member of the Academy of Crusca, urged Federico Cesi (1585-1630) to take him into the Lyncean Academy. His request was granted and Cesi himself reports his approval of the "person suggested" due to the praiseworthiness of his "genius, valor and quality".
Salviati set out for Spain, probably over an unresolved question of honor with Bernardetto Medici, and died in Barcelona on March 22, 1614, when he was only 32.
As a tribute to the admiration Galileo felt for Filippo Salviati he chose to call the alter-ego of his later works by the name of his estimable friend.