National Mortgage Crisis of the 1930s

The National Mortgage Crisis of the 1930s was a Depression-era crisis in the United States characterized by high-default rates and soaring loan-to-value ratios in the residential housing market. Rapid expansion in the residential non-farm housing market through the 1920s created a housing bubble inflated in part by ad hoc innovation on the part of the four primary financial intermediaries – commercial banks, life insurance companies, mutual savings banks, and Building & Loans (thrifts). As a result, the federal overhaul stemming from New Deal legislation gave rise to a paradigmatic shift in mortgage lending, popularizing longer-term maturity, fully amortizing mortgages and creating a thick secondary market for mortgage-related securities.

Lending was dominated by four financial intermediaries – commercial banks, life insurance companies, mutual savings banks, and thrifts (also called Savings and Loan Associations, or S&Ls) – though only life insurance companies operated interregionally. Mutual savings banks and commercial banks held commanding market shares in specific regions – New England and Mid-Atlantic cities, and in the West, respectively – but were limited elsewhere. Thrifts, by contrast, expanded to all corners of the country by the end of the 1920s, but functioned predominantly on the local level.

In addition to their geographic range of influence, the four intermediaries differed in their preferred mortgage terms. Commercial banks, life insurance companies, and mutual savings banks typically offered 5-year balloon mortgages at a loan-to-value ratio of 50%. As with any bubble environment, borrowers and lenders alike expected asset prices to rise ad infinitum and tended to continually refinance at maturity, exposing themselves to the clear danger of default and resulting institutional insolvency in the event of tightened credit.

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