Ian Matthias Bavitz (born June 5, 1976), better known by his stage name Aesop Rock, is an American hip hop recording artist and producer residing in Portland, Oregon. He was at the forefront of the new wave of underground and alternative hip hop acts that emerged during the late 1990s and early 2000s. He was signed to El-P's Definitive Jux label until it went on hiatus in 2010. betterPropaganda ranked him at number 19 at the Top 100 Artists of the Decade.

He is a member of the groups The Weathermen, Hail Mary Mallon (with Rob Sonic & DJ Big Wiz), The Uncluded (with Kimya Dawson) and Two of Every Animal (with Cage). Regarding his name, he said: "I acquired the name Aesop from a movie I had acted in with some friends. It was my character's name and it sort of stuck. The rock part came later just from throwing it in rhymes."