 When his parents divorced, Casagrande and his mother moved to West Allis, Wisconsin and later Whitefish Bay.After graduating from Whitefish Bay High School as a multisport student athlete, Casagrande earned a bachelor's degree from the University of Wisconsin in 1938, and completed a doctorate in anthropology at Columbia University in 1951.He began teaching at the University of Illinois at Urbana–Champaign in 1960, and co-founded the school's department of anthropology alongside Julian Steward, Oscar Lewis, and Kenneth L. Hale.