After his training in Strasbourg, Baldung, from a scholarly family of a humanist bent, worked in Nuremberg between 1503 and 1508 as an apprentice to Albrecht Dürer, who became a lifelong friend. Since around 1505 there were three apprentices there with the first name Hans, he was given the nickname 'Grien' (Green), which he would later include in his monogram 'HBG'. In 1509 he returned to Strasbourg, where he acquired citizenship and opened a flourishing workshop. From 1512 to 1517, he worked on the retable for the high altar in the Freiburg cathedral, his most important work. In 1515 he was involved with Dürer, Cranach and Altdorfer on the marginal drawings for the prayer book of Maximilian I. From 1517 to his death, he was again active in Strasbourg and also held public offices occupied with mathematical and fortification issues. His work was initially heavily influenced by Dürer, his teacher, but soon developed wholly independently and in a diversity of subject matter. His oeuvre is comprised of altarpieces, portraits, mythological scenes and allegories. His depictions of nudes and witches make up a characteristic portion of it. From the 1520s onwards, he increasingly exhibits Mannerist tendencies. With some 250 sheets, Baldung left behind the most extensive draughtsmanly oeuvre of his epoch, barring those of Dürer and Hans Holbein the Younger.