The centaur is one of the  most well known creatures.  The half man (chest and head), half horse (torso and legs) creatures are often depicted as violent and war-like.  

An example of a centaur is Chiron, a mythical creature, who was a wise centaur with a lot of knowledge about music, medicine and archery.  He was the teacher of Jason, Hercules, and Achilles.  Chiron was very wise and kind but he died when Hercules accidentally hit him with a poison arrow.  This is from the Greek myth about Hercules.     

The idea of a centaur might have came from the Thessalians, who were among the first tribes to fight on horseback.