The director of the Census Bureau doesn’t often pay house calls for census enumeration, but, in the spring of 1940, William Austin stopped by the White House to find out who was home. Franklin Roosevelt himself helped fill out the form in which he listed nine in a household that included personal secretary Marguerite “Missy” LeHand, one cousin, a governess, and four “Negro servants.”

The page that FDR helped complete is one of 3.9 million images of the 1940 Census now available online at the National Archives website and Archives.com. When Allen Weinstein became the official archivist of the United States in 2004, one of his primary goals was to increase the digitization and public availability of holdings. But the government agency lacked the resources to tackle the massive job, so he put in place innovative public/private partnerships to get the work done.

The 1940 Census is the largest collection of digital information ever released by the National Archives, and it's the first time they have released an official decennial census online. The huge national service project involved some 300,000 volunteers, as well as corporate partners who covered most of the bill.  It made internet history as one of the largest and most innovative uses of crowd-sourcing episodes up to that time. 

Federal law restricts access to census records for 72 years—one concern being identity thieves—so eager researchers will have to wait another ten years before they can explore the 1950 data.