Barlow moved permanently to Mexico around 1943, where he taught at several colleges, and in 1948 became chairman of the anthropology department at Mexico City College and a distinguished anthropologist of Indigenous Mesoamerican culture. He taught classes at Mexico City College, to mostly American students who were mostly there under funding from the post-war G.I. Bill. The famous writer William S. Burroughs, who lived in Mexico from 1950 to 1952, studied the Mayan Codices under Barlow in the first half of 1950. Burroughs went on at least one field trip with him to the Temple of Quetzalcoatl in Teotihuacan. The Mayan symbolism and political structure he found there later featured heavily in Burroughs' fiction.