Tiberio Tinelli was one of the most important Italian portrait painters of the early 17th century. The contemporary biographers Marco Boschini and Carlo Ridolfi already wrote about him in detail, but the discovery of the account book of Tinelli's workshop has enabled researchers to further explore his biography and his artistic activities. According to the information contained, Tinelli was an apprentice of Giovanni Contarini in Venice for a short time before moving to the workshop of Leandro Bassano. He remained with Bassano from 1604 to 1618. In 1618, Tinelli began keeping the account book. In the early years of his independence, he mainly carried out commissions for monasteries and churches, but soon specialised in portraits. Tinelli kept his account book until 1634, during which time he executed 298 paintings, mostly small-format portraits. Tinelli received some of his biggest commissions in the following years. The French King Louis XIII knighted him with the order of Saint Michael and tried in vain to lure him to Paris as a court painter. Instead, Tinelli accompanied a Venetian envoy to Mantua in 1638 and painted portraits of the ruling Gonzaga family. After returning to Venice, Tinelli fell ill with a fever and died a few days later. Tinelli's detailed portraits reveal the influence of the works of van Dyck, Rubens and Bernardo Strozzi.