NEW YORK >> Americans are in for a cyber-surprise on Wednesday: They’ll be able to plug family names into an online 1940 U.S. census and come up with details about the lives of New Yorkers — from Joe DiMaggio and Jacqueline Bouvier Kennedy to their own relatives.   

Starting after midnight, it will no longer be essential to provide exact addresses from seven decades ago to look for a New York connection.  

With names, free searches of the 1940 U.S. census first made public in April will unlock personal information about residents of New York — then the largest U.S. state and an immigrant hub from which people moved all over the country.

Census experts say the New York data is of national interest because tens of millions of Americans have roots in this gateway to the United States through Ellis Island, and many can now dig for more personal information.

“That’s the exciting aspect about this — the ability to search the lifetime of our mothers and fathers,” said Debra Braverman, a New York-based independent forensic genealogist with clients seeking information for trust funds and estates.

When the census was first released, “if you didn’t know exactly where someone lived in 1940, you couldn’t find them,” Braverman said.

Indexing by name is crucial to cracking the until-now closed book of that year’s census, which by law could not be released for 72 years and is therefore the most recently available one.   

This U.S. census leads to China.

Some of the work of transcribing handwritten census records into a computerized index was done by workers in an office outside the southern city of Dongguan with “very strong character recognition abilities,” said Todd Jensen, who heads the document preservation service at Ancestry.com, a Provo, Utah-based family history company that’s releasing the online New York census for 1940 using their new name index.

“Given the complexity of their own language, reading and recognizing characters from other languages comes easier,” he said.

Also Wednesday, another historic treasure trove appears on the Internet for the first time: census information compiled separately by New York state for 1915 and 1925, indexed by name. These records include details about famed personalities such as Lauren Bacall, Al Capone, Franklin Roosevelt and Harry Houdini, who according to the 1925 census was born in the United States, even though most biographies say he was born in Hungary.  

The interest in roots is so intense that 37 million hits temporarily crashed the National Archives provider site when the 1940 census was released on April 2. Many who logged on hoping for results hit the wall, frustrated for lack of specific locations required for results.

Braverman, a Manhattan resident, uncovered details about her 84-year-old father’s family because he remembered his family’s Brooklyn address before his bar mitzvah in 1940, when he was 13.

“His memory was spot on,” his daughter said.

But the Brooklyn childhood address her mother remembered didn’t match, so they will try to find the information again this week.  

Former New York Mayor Ed Koch hit the jackpot when it came to his family history, which is contained in all three censuses — the federal one, as well as the New York ones from 1915 and 1925.

The 87-year-old Koch participated in a preview search conducted by Ancestry.com, which is making all three census records available online.  

His said his father came from Europe, alone at age 16, eventually raising a family in a Bronx apartment. For years, “I told people that we lived in abject poverty,” he said. A series of census records from the time would prove him wrong.

They showed that the Depression-era rent for the Kochs’ five-room Bronx apartment was $75 a month, “and that was a lot of money at the time,” Koch said.   

“All my life, I was telling people I was very poor, but I learned we did not live in abject poverty; I was born into a middle-class family,” he said.  

The New York world of the 1940 census includes names that later became famous, including Katharine Hepburn, John D. Rockefeller Jr., J.D. Salinger, Kennedy and Ella Fitzgerald.

The 1940 census by name index will be available for all states possibly as early as this fall.  

While New York is the biggest state whose census records are already name-indexed, a number of smaller states also have been made name-accessible by Ancestry.com and two other companies, FamilySearch.org and MyHeritage.com.

New York state censuses for 1915 and 1925 are available online for the first time via a link that says “find family history for free” to anyone providing a New York ZIP code and email address.

The state censuses show “every New Yorker from the famous to the infamous to everybody in between,” said Kathleen Roe, director of archives and records management at the New York State Archives.  

A perfect example of this melting pot is Babe Ruth, who at 17 appeared in the 1925 census as “George H. Ruth,” living by the Grand Concourse near Yankee Stadium, which would later be dubbed “The House That Ruth Built.” The Ruth family neighbor was Joseph Weinstock, an Austrian immigrant working in manufacturing and his Russian-born wife, the census shows.

“So here was the future American baseball hero living next door to an immigrant family making it in the United States,” Roe said. “What a great American story! And that’s what you can find out walking through a neighborhood with census records.”  

The censuses released this week offer “one of the greatest collections of historic voices you’ll ever find,” said Roe, adding that if read together, they trace whole families as they move around.  

The census data also include such information as occupation, whether immigrants were naturalized citizens, and whether they owned or rented their homes — in other words, sketches of communities, said David M. Kleiman, president of Heritage Muse Inc., a New York-based genealogy technology firm.

“What we’re all looking for is the story of the family — what made my grandparents the way they were, which made my parents the way they were, which made me what I am,” he said.

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Ancestry.com: www.ancestry.com/newyork
New York State Archives: www.archives.nysed.gov

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