"Racial redlining" acquired formal governmental backing in the 1930s when the Home Owners' Loan Corporation (HOLC), a federal agency, was charged with establishing "residential security maps" for 239 US cities. These secret maps, composed with input from "competent local real estate brokers and mortgage lenders," ranked zones within cities in terms of their desirability for residential investment. The central criterion underpinning the ranking concerned their ethnoracial character. The residential security maps coded affluent and desirable lending zones green and blue, less affluent and less desirable areas yellow, and zones inhabited by blacks--and so deemed undesirable--with the alarmist, high alert red. In 1936, HOLC guidelines made explicit these color-coded residential security maps.

The security maps, a central technology of residential planning and management across US cities from the late 1930s on, became the basis across many years to follow for denying mortgage loans by government and private banks especially to black home seekers and in black neighborhoods. They thus fueled racial residential segregation, urban abandonment, and ultimately capital flight, thus hyper-concentrating racial poverty, slum conditions, and urban blight. Today's gated communities are essentially privatized modalities of redlining, segregating communities informally extended.

Color-coded maps were produced in the 1930s and 1940s for almost every city in America to delineate—both to describe and determine—what urban areas were to be developed for appealing, secure, and wealth-producing housing for eligible, racially coded population groups, and what areas were to be avoided, ultimately left undeveloped or underdeveloped. These maps were accompanied by municipal regulations, mortgage company directives, and insurance company missives from the 1930s onwards directing investments and restricting what urban areas would be available for development, gentrification, and support. As the maps and accompanying materials make explicit, public and private mandates combined to code urban housing development and the basis of ensuing suburban formation in straightforwardly racially segregationist terms.

The archive reveals, perhaps unsurprisingly for anyone with knowledge of the field but still disturbingly, even chillingly, that those urban areas that remain racially segregated today tend largely to be those that were historically redlined from the mid-1930s onwards. The color-coding of the maps, we note in passing, form the basis also of the contemporary Homeland Security alert system, thus linking histories of urban segregation abstractly to more recent patterns of national restriction.

The maps, regulations, and missives are collected at the National Archives. With generous support from the Institute for Museum and Library Services we have constituted a team to digitize the maps and materials, and to develop an easily searchable data base hyper-linking the color-coded maps and written directives generated through Google maps. We began constituting the digital archive of redlined neighborhoods by focusing on the maps and accompanying materials for eight Californian cities (San Diego, Sacramento, Los Angeles, San Francisco, Oakland, San Jose, Stockton, and Fresno). We eventually hope to expand the archive to include other US cities and additional capabilities: this will form the basis of a new and enhanced interface, which we refer to as "iRACES." The expanded data base will be available through http://www.uchri.org in due course. In the meantime, the viewers' feedback through Vectors would be much appreciated.

The archive will ultimately be hosted on the HASS Grid, a grid network Richard Marciano and David Theo Goldberg have been working with a dedicated team to complete for system-wide Humanities, Arts and Social Sciences across the University of California, where the materials will be available for broad public consultation and use. The archive, we believe, has profound implications for research related to urban studies, history, ethnic studies, geography, American literatures of the urban, cultural studies, conceptions of race and racism, as well as for legal studies and fair housing consideration.