Agostino Chigi (29 November 1466 – 11 April 1520) was an Italian banker, and patron of Renaissance art. He was Rodrigo Borgia's regular banker, and also engaged in business dealings with Juan Borgia the Elder, another member of the Borgia.
Agostino was born in Siena, the son of prominent banker, Mariano Chigi, and in 1487 moved to Rome to aid his father. There he lent large amounts of money to Pope Alexander VI (and other rulers as well), and he strayed from common mercantile practice after obtaining several monopolies.
Work with Pope Julius II
After the death of Rodrigo Borgia and his short time successor, Chigi became Pope Julius II's expenses attendant upon his election, the latter awarded him, and he linked Chigi to the Della Rovere family and made him the Apostolic Camera's treasurer and notary. The two remained close allies, with Agostino occupying the Pope during his military campaigns in 1506 and 1510, and in 1511 Agostino was sent to Venice to support the papal forces in the War of the League of Cambrai.