If you thought the 1980 LISP Conference was the first Lisp conference, you were wrong. The 1980 conference was organized by Ruth E. Davis and John R. Allen and was held at Stanford University, with sponsorship by Stanford, Santa Clara University, and The LISP Company. It led to the biennial ACM-sponsored Lisp and Functional Programming Conference. But more than 16 years earlier, the First International LISP Conference was held at Universidad Nacional Autónoma de México (UNAM) in Mexico City, from December 30 to January 4, 1964. No proceedings was published for the conference, but I have been able to assemble some information about it.