The Frankfurt School, or officially the Institute for Social Research, is a school of neo-Marxist crazies. It included Adorno, Benjamin, and other names commonly referenced by pretentious humanities people. The name "Frankfurt School" refers to the fact that the institute was first located at the University of Frankfurt in Germany.
After the Nazis took power, most of them fled Germany and set up shop at Columbia. The institute was located in a rowhouse on 117th Street, which was demolished to make way for the law school and East Campus.
They loved it here so much that they left for California after a couple years and then back to Germany at the first opportunity.
Andreas Huyssen teaches a class about the Frankfurt School.