Schoenfeld received his Ph.D. in 1944 from the University of Pennsylvania under the direction of Hans Rademacher. He met Josephine M. Mitchell when they were both professors at the University of Illinois in the early 1950s. After they married, the University would no longer allow Mitchell to teach, so the couple both resigned their positions and eventually settled at Pennsylvania State University. In 1968 the couple moved to the University of Buffalo where they remained until their retirements in the 1980s. Schoenfeld is known for his work in analytic number theory.
From the guide to the Lowell Schoenfeld Papers, 94-265., 1965-1969, 1990, (Archives of American Mathematics, Center for American History, The University of Texas at Austin)