Vitruvius was a Roman architect known for his lengthy discussion in the treatise De architectura about perfect proportion in architecture and the human body. His work led to the famous Renaissance drawing by Leonardo da Vinci of Vitruvian Man which represents ideal human body proportions.
In addition to da Vinci's many talents as a Renaissance man it is highly likely he was vegan. He wrote that his diet would not let his body be a "tomb for other animals, an inn of the dead - a container of corruption."
Upon encountering vegetarians in India, Italian explorer Andrea Corsali wrote to his and da Vinci's mutual patron Giuliano de' Medici that they "do not feed upon anything that contains blood, or do they permit among them any injury be done to any living thing, like our Leonardo da Vinci."
A fascinating discussion and video about da Vinci and veganism is here as part of a series on the history of veganism created by Bite Size Vegan.