Not only was Pythagoras, the mathematician and philosopher, a vegetarian but vegetarians were actually called Pythagoreans up until the 1800s.
Pythagoras was born on the Greek island of Samos between 580 and 572 BC and was the first man to call himself a philosopher, or lover of wisdom.
After years spent travelling he realised that his native land offered him few opportunities to expound his wisdom and settled instead in Crotona, Italy, where he was impressed by the liberal-mindedness of the inhabitants. Here, with his followers, he influenced the development of mathematics, music and astronomy, urging all the citizens to strive to lead virtuous lives, influenced by a love of culture.
Part of this virtuous life was to abstain from eating meat. He is reported to have said (none of his own writings survive) that ‘as long as Man continues to be the ruthless destroyer of lower living beings he will never know health or peace. For as long as men massacre animals, they will kill each other. Indeed, he who sows the seed of murder and pain cannot reap joy and love.’
He died in Metapontum between 500 and 490 BC at around 90 years old from unknown causes.