The Redlining Maps of the 1930s and the Neighborhoods They Shaped

The maps are beautiful in the way old government documents sometimes are: hand-tinted, carefully lettered, each city divided into neat zones of green, blue, yellow and red. They were drawn in the second half of the 1930s for a New Deal agency called the Home Owners' Loan Corporation, which had been created in 1933 to rescue homeowners from foreclosure during the Depression. Local real estate agents, appraisers and lenders helped grade each neighborhood. Green meant "best." Red meant "hazardous." Attached to each zone was a short description, and in neighborhood after neighborhood across the country the descriptions named the presence of Black residents, and sometimes immigrants or Jewish families, as a reason for a lower grade. For decades the maps sat in the National Archives. When researchers and then the public rediscovered them, they became the most famous image of American housing discrimination. The question they raise is harder than it first looks: did the maps cause the decline of the neighborhoods they marked, or did they simply write down a pattern that already existed?

In short: The HOLC maps are real, racially explicit and closely matched by present-day gaps in wealth, health and home values. Economists still debate how much the maps themselves caused, as opposed to the Federal Housing Administration, private lenders and earlier discrimination. Here's the argument: the debate is worth having, but it changes who did the damage, not whether it was done.

What the Home Owners' Loan Corporation actually did

It is worth starting with what is not in dispute. The Home Owners' Loan Corporation was, for its first years, a rescue program. It bought defaulted mortgages from banks and refinanced them on easier terms, saving many families from losing their homes. It made loans in neighborhoods of every grade, including those later colored red, and it lent to Black homeowners.

The maps came later, as part of a project to assess the risk of lending in different parts of cities. Between roughly 1935 and 1940, the agency produced residential security maps for more than two hundred cities. Appraisers rated neighborhoods on housing age and condition, access to transportation, the incomes of residents and, explicitly, their race and ethnicity. The maps are now available to anyone through the Mapping Inequality project at the University of Richmond, which digitized them along with the area descriptions.

Reading the descriptions today is jarring. Appraisers wrote about the "infiltration" of Black families as a threat to property values in plain bureaucratic prose. Neighborhoods with Black residents were almost always graded D, regardless of the condition of the houses.

That is the record. The debate is about what happened next.

The case that the maps caused harm

The common account, popularized in books, journalism and public exhibits over the past decade, goes like this. Banks and government agencies used the maps to decide where to lend. Red neighborhoods were starved of credit. Without mortgages, families could not buy or improve homes, property values fell, owners stopped investing, and decline became a self-fulfilling prophecy. Decades later, those same neighborhoods have lower home values, lower incomes, more pollution and worse health outcomes.

There is serious economic research supporting a version of this. A study by economists at the Federal Reserve Bank of Chicago, Daniel Aaronson, Daniel Hartley and Bhashkar Mazumder, compared neighborhoods just on either side of map boundaries, on the logic that blocks right next to each other should be similar except for the grade they got. They found that areas on the lower-graded side of a boundary saw more racial segregation and lower homeownership and home values in the following decades than areas just across the line. Other researchers have linked historically redlined areas to higher present-day temperatures, more air pollution and less tree cover, though those studies show association more than proof of cause.

That evidence is the strongest case for the maps as a cause. It suggests that being labelled red, rather than just being a poor or Black neighborhood, had an effect of its own.

The case that the maps recorded harm

Another group of economists, including Price Fishback and several colleagues, has examined the same history and reached a more cautious conclusion. They make several points that deserve a fair hearing.

First, the maps were drawn after the agency had made most of its own loans, so they could not have guided much of its lending. Second, the maps were not widely distributed; there is limited evidence that private banks used them directly. Third, the neighborhoods graded red were, in most cases, already poorer and already segregated before the maps were drawn, because of decades of racial covenants, violence, discriminatory practices by private lenders and real estate agents, and local government decisions. The maps, in this view, were a symptom of a discriminatory system, written by members of the real estate industry who were recording the prejudices they already held.

Fishback and his co-authors argue that the larger federal culprit was another New Deal agency, the Federal Housing Administration, created in 1934. The FHA insured mortgages, which made it the engine of the postwar suburban boom, and its underwriting manual told appraisers to consider racial composition and recommended restrictive covenants to protect property values. The FHA's own practices steered insured lending away from Black neighborhoods and toward new white suburbs on a far larger scale than anything the HOLC did.

Researchers in this camp have also noted that some of the long-term gaps found near map boundaries existed, at least in part, before the maps were drawn, which makes the maps' own effect harder to isolate.

Why the distinction matters, and why it does not

To someone outside the field, this can sound like academics arguing about which brick in a wall did the most damage. But the distinction matters for two reasons.

The first is accuracy. Progressives make a stronger case when they get the history right. If the popular story places all the blame on maps that most banks may never have seen, it hands critics an easy rebuttal and lets the bigger players off the hook. The FHA, the private lending industry, real estate boards that wrote ethics rules forbidding agents from introducing Black families into white areas, and local governments that used zoning and urban renewal to contain Black neighborhoods all had roles that were arguably larger. Telling the story precisely puts responsibility where it belongs.

The second is policy. If the problem was one set of maps, one might think it ended when the maps were retired. If the problem was a whole system of public and private practices, then the remedies have to be as broad as the system.

Here is the part both sides of the debate agree on: the federal government participated in, endorsed and in significant ways reinforced racial discrimination in housing. The HOLC maps were one expression of that; FHA underwriting was another. Whether a particular red line caused harm or recorded it, the people living on the wrong side of it faced closed doors from many directions at once. The debate is over the distribution of blame, not over the existence of the injury.

What filled the gap when banks stayed away

When ordinary mortgage credit is unavailable in a neighborhood, demand for homes does not vanish. Someone else fills the gap, usually on worse terms. That is one of the most important and least discussed consequences of the lending patterns of the mid-twentieth century.

In Chicago in the 1950s and 1960s, many Black families who could not get conventional mortgages bought homes "on contract." A speculator would buy a house cheaply, often from a white owner anxious to sell as the neighborhood changed, and resell it to a Black family at a steep markup. The buyer made monthly payments but did not get the deed until the full price was paid. Miss one payment and the seller could evict the family and keep everything they had paid, then sell the house again to the next family. In the late 1960s, a group of Black homeowners on the city's West Side organized as the Contract Buyers League, staged payment strikes and sued, and drew national attention to the practice.

A related practice was blockbusting. Real estate agents would spread fear among white owners that Black families were about to move in, buy their homes cheaply in the panic, and sell them to Black buyers at inflated prices. Neighborhoods turned over in a few years, and the agents profited on both ends.

Neither practice depended on a colored map. Both depended on a credit system that treated Black neighborhoods and Black buyers as unworthy of ordinary loans, which pushed families toward lenders and sellers who could charge whatever they liked. That is a pattern worth recognizing, because it recurred later. The subprime loans of the 2000s were, in a sense, a modern version: credit that arrived in neighborhoods long denied it, but on terms designed to extract wealth rather than build it.

This is also where the economists' debate looks less important than it first appears. Whether the HOLC maps directly guided lending or merely reflected the industry's views, the system those maps represented produced exactly these outcomes: families paying more for less, and wealth flowing out of the neighborhoods that most needed it.

The laws that came later

Federal law did eventually change. The Fair Housing Act of 1968, passed days after the assassination of Martin Luther King Jr., banned discrimination in the sale, rental and financing of housing. The Home Mortgage Disclosure Act of 1975 required lenders to report where they made loans, which made discrimination easier to see. The Community Reinvestment Act of 1977 required banks to meet the credit needs of the communities where they took deposits, including low- and moderate-income neighborhoods.

Those laws helped, and they also had limits. Enforcement has risen and fallen with administrations. Lending gaps by race persist, and the subprime lending boom of the 2000s, which targeted many Black and Latino neighborhoods with high-cost loans, wiped out a great deal of the wealth those families had built. The racial gap in homeownership, which is the main way American families build wealth, remains wide.

There is also a newer debate about appraisal bias: studies and individual cases have found homes in Black neighborhoods, or owned by Black families, appraised for less than comparable homes elsewhere. Federal regulators and the appraisal industry have taken steps on this in recent years, though how far those efforts continue under the current administration is uncertain.

It is also worth noticing how the debate itself has been conducted. Economists on both sides have published their data and methods, responded to one another's criticisms and refined their estimates. That is how a contested question about history should be handled, and it is a useful model for public argument. The public conversation would be better if it kept the same spirit: hold the claim to the evidence, and change the claim when the evidence requires it.

Where the maps still show up

One reason the maps have such a hold on the public imagination is that you can lay them over a modern map and see the outlines. Freeways built in the 1950s and 1960s often cut through neighborhoods graded red. Industrial zones cluster there. Tree cover is thinner. Home values are lower.

Not all of that is the maps' doing. Some of it is the federal highway program, some is local zoning, some is decades of disinvestment from many sources. But the overlap is a reminder that history in cities is cumulative. A decision made in the 1930s narrows the choices of the 1950s, which narrow the choices of the 1990s. Breaking that chain requires deliberate investment in the places that were passed over: housing, transit, parks, schools and cleaner air.

That kind of investment has supporters across the political spectrum when it is described as rebuilding neighborhoods rather than as a racial program, and some of the most successful efforts have been led by local residents of every background. The racial justice page follows those efforts and the ongoing fight over fair lending.

What you can do

The maps are history, but the decisions that follow them are made every year. Here is how to get involved.

• Look up your own city. Mapping Inequality makes the 1930s maps available online. Compare them with your neighborhood today, and with the polluting facilities in your ZIP code, which list EPA-regulated sites and their violations.
• Comment on fair lending and housing rules. When federal agencies propose rules on lending, appraisals or fair housing, the public comment page lists the open rules with a guide to writing a comment.
• Support local fair housing groups. The organizations directory lists housing and civil rights nonprofits in every state, including fair housing groups that test for discrimination and help people file complaints.
• Follow the housing story. The housing and homelessness page covers lending, zoning and the neighborhood investment fights where this history plays out.

The colored maps were drawn by people who believed that Black neighbors lowered property values, and who were in a position to make that belief come true. Whether their pens or someone else's did the most damage, the work of repair belongs to all of us now.