AUDIE CORNISH, HOST:
It's ALL THINGS CONSIDERED from NPR News. I'm Audie Cornish.
ROBERT SIEGEL, HOST:
And I'm Robert Siegel. A national treasure is scheduled to be revealed on Monday.
UNIDENTIFIED MAN: In April 1940, 120,000 census takers are radiating in a carefully planned pattern across America to complete, in a single month, the greatest inventory of the world's greatest democracy.
SIEGEL: And now that the legally mandated 72 years have passed, we get to see the names, addresses, jobs and salaries of all the people who were counted. This lifting of the veil takes place every 10 years. And William Maury, chief historian of the U.S. Census Bureau, says this census offers some especially interesting insights into America.
WILLIAM MAURY: The 1940 census was very close to the end of the Depression, but it was also right at the beginning of all the uncertainties associated with World War II. The census itself tells terrific stories about what we were as a people and what we are as a people now, how we've changed and what we've done and things of that nature.
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SIEGEL: What kind of a country was this in 1940?
UNIDENTIFIED MAN: Its more than 130 million free people, its 33 million homes, its seven million farms, its vast panorama of other resources.
SIEGEL: And how big a deal is the release of what those 120,000 census takers found in 1940?
JEANNE BLOOM: It is a huge event. It's kind of like the Super Bowl for genealogists.
SIEGEL: Jeanne Bloom is a member of the Chicago Genealogical Society. Her interest is not just personal. She does detective work for the U.S. Army, looking for the survivors of soldiers who died in action, tracing family records.
BLOOM: And what I do is I locate living family members of soldiers that were missing in action during World War II, the Korean War, Vietnam, whose remains were never recovered, identified and returned to the family.
SIEGEL: Now, apart from your professional interest in the data in the 1940 census, what about your own family or your own curiosity, for that matter? What are the things that you're looking for, personally?
BLOOM: I'm really excited because this is the census for the first time that my mother will appear. She was born after the 1930 census, so I'm going to be able to see her family on the farm in rural Kansas with what her brothers and sisters are doing, so I've got great excitement about that.
SIEGEL: Genealogists and millions of Americans for whom genealogy is a hobby, speak of seeing people in the census. By 1940, of course, we're talking about people whose lives were likely documented in photographs and letters, but this is official documentation.
Ann Fleming, the St. Louis genealogist, puts it this way.
ANN FLEMING: I always think of the census as the border of the family jigsaw puzzle. And you put this border together and then you fill in other information in the center, but a lot of good starting points come from the census records.
UNIDENTIFIED MAN: Thousands of operators will sort and tabulate the millions of cards almost entirely with machines, mechanical marvels of accuracy and speed.
SIEGEL: This year's release of the 1940 data is notable for its own mechanical marvels. The National Archives is offering it all directly online for the first time. That makes life easier for Jamesetta Hammons of the California African American Genealogy Society. She recalls waiting for release of details of the 1920 census 20 years ago.
JAMESETTA HAMMONS: I drove to Laguna Niguel, where the National Archives regional branch is located - or was located at that time - and I slept in my car in the rain so that I could be the first in line to have access. Someone jumped ahead of me and so, for the 1930 census, I was privileged to be the first in line and I was actually offered the opportunity to open the cabinets and pull out the drawers that held these gold nuggets for researchers.
SIEGEL: Well, tell me about your own personal curiosity. What is it, perhaps, out of your own genealogy, that you will be most looking for in the 1940 census?
HAMMONS: Well, my curiosity about my family has to do with health issues, where they lived in 1940 and, of course, their life experiences.
SIEGEL: And what is, specifically, a question that you at least hope will be answered once you get a look at the 1940 census?
HAMMONS: I'm hopeful that I will find where my parents and my one grandfather lived in 1940. On the 1940 census, one of the things that's exciting to me is that there is a question that's asked, if the person lived in a different location in 1935, that that location is given and one unique thing: if the person lived on a farm.
SIEGEL: And since there's the information about 1935 put together with the 1930 census, some families will actually get a, you know, picture in motion of their family in the 1930s.
HAMMONS: That's correct. There seems to be some stability in my particular family where they lived the same place for long periods of time.
SIEGEL: In 1940, the Census Bureau, in its film, told us this about the census.
UNIDENTIFIED MAN: You can not know your country unless your country knows you.
SIEGEL: But does our country really know us from the census? I asked Census Bureau historian William Maury. Is all that census information - which is self-reported and collected by all those census takers - is it the gold standard of historical data or something less? Are the numbers sometimes not entirely reliable?
MAURY: Personally, very much the latter, particularly when it's all self-identification. You can say anything. You know, you can say you're Chief Sitting Bull's son or something like that. You can come up with all kinds of things. One of the things that we say when people call us, we just say, well, you know, this is what's on the record.
SIEGEL: So it's not entirely an objective picture of the country in 1940. It's more like a kind of a gigantic national self-portrait in 1940.
MAURY: In a way, yes. But if you take all the sort of discreet parts of it and jumble them together, it's probably pretty accurate, so it's certainly not absolutely certain and, if you're dealing with individuals for it, it's certainly not certain.
UNIDENTIFIED MAN: Official census questions must be answered, but the census taker is sworn to strict confidence with heavy penalties for violation of his oath.
SIEGEL: Details of the 1940 census will appear online on Monday. You can get links to the National Archives information at our website, NPR.org.
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