How the City Survey’s Redlining Maps Were Made: A Closer Look at HOLC’s Mortgagee Rehabilitation Division

The infamous “security maps” made in the 1930s by the Home Owners’ Loan Corporation (HOLC), rating supposed mortgage lending risk in urban neighborhoods across the United States, have long been considered the quintessential expression of racist redlining policy. However, a number of misunderstandings and unwarranted speculations about how these maps were made and used have proliferated. Using previously unexamined correspondence, this article establishes that HOLC could not have used the maps for loan denials, did share them with the Federal Housing Administration but not with private industry, and highly improvised their production with numerous methodological inconsistencies, including with regard to race.