He was first taught in his native Arezzo by the little-known French glass painter and fresco painter, Guillaume de Marcillat (1475-1529 or 1537). By 1524, he had moved to Florence, where he worked for Andrea del Sarto (1486-1530), in whose studio he became acquainted with Francesco Salviati (1510-1563). During his early training in Florence, he met Michelangelo (1475-1564) and Baccio Bandinelli (1493-1560). In 1527, Vasari returned to Arezzo, following the political turmoil in Florence consequent upon the expulsion of the Medici in that same year, travelling later to Pisa and Bologna. At the invitation of Cardinal Ippolito de' Medici, Vasari travelled to Rome in 1531, returning to Florence in the following year in order to enter the service of Duke Alessandro de' Medici. In 1536, Vasari collaborated on the temporary decorations for the triumphal entry into Florence of the Emperor Charles V. After Alessandro's murder in 1537, he for a time left the employment of the Medici and, in this same year, was engaged on his first important independent commission, the decoration of the presbytery of the monastery church of Camaldoli, in the Northern Casentino. Shortly thereafter, he travelled widely in Italy engaged upon various commissions, using his journeys to gather together the notes and records for his "Vite". Among his many important works of this period are the decoration of his house at Arezzo (begun 1542); paintings at Monte Oliveto, Naples, including the refectory (1544-1545); and the decoration of the gran salone of the Cancelleria, Rome (1546). He was also employed in Rome by a succession of popes, including Julius III (1550-1555), Pius IV (1559-1565) and Pius V (1566-1572). At Michelangelo's death in 1564, Vasari was one of the members of the Accademia del Disegno, Florence, who partook in the decoration of S. Croce for the great artist's funeral exequies.
Vasari is best known as the author of "Le vite de' più eccellenti pittori, scultori, e architettori", the greatest single source for Italian Renaissance art, the second edition of which was published in Florence in 1568. He was also a painter and architect of great distinction, working intermittently over many years for the powerful Medici family in Florence, sometimes directing their most ambitious artistic projects, such as the pictorial decoration of the Palazzo Vecchio, and as pioneer collectors of Old Master drawings (Turner, N.: From Michelangelo to Annibale Carracci. A century of Italian drawings from the Prado, Art Services International-Museo Nacional del Prado, 2008, p. 92).