In 1950 he received a Bachelor's degree in Anthropology from the University of California, Berkeley, studying under Alfred L. Kroeber and Carl Sauer.
This exposure to museum artifacts convinced him that material culture is a valuable source for historical research.
Much of his early career was marked by his heated disagreements with Betty Meggers over the respective roles of diffusion and local development.
Using their understanding of linguistics, they suggested that the West Coast was an important corridor and had been occupied earlier than generally accepted today.
Lathrap was a professor of anthropology at the University of Illinois when he died of an embolism following abdominal surgery in May 1990.