The centaur Chiron raised Achilles at the request of Achilles' mother. This centaur, half man, half horse, was, in classical mythology, a famous teacher to various heroes and gods. Attributes in the oil sketch, such as lyre, arrow and hunting horns, refer to his lessons in music and poetry and hunting. He also gave lessons in horse-riding and medicine, which is symbolised by the god Aesculapius, who is depicted on the left as a hermit. This is the second in a series of eight oil sketches by Rubens, based on the life of the Greek hero Achilles. Rubens designed four series of tapestries, and all four were executed. That was an expensive and time-consuming procedure in which oil sketches like these were just the first step. They were followed by larger painted models, which preceded full-size cartoons for the weaver which were ten times the size of the initial sketches and were typically painted by assistants. It is hard to imagine that a project of that kind could be undertaken without a patron, but in three of the four cases we do not know who this was. The last series was made around 1630, and all eight of sketches have survived. Seven are in Museum Boijmans Van Beuningen. They chronicle the life of the Greek hero Achilles from his baptism in the Stynx, one of the legendary rivers of the underworld. That baptism would have made him immortal if his mother had not held him by the heel while immersing him. That proverbial unprotected Achilles' heel proved fatal, as can be seen in the eighth and last panel.