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Find more Bertelsen relatives and grow your tree by exploring billions of historical records. Taken every decade since 1790, the U.S. Federal Census can tell you a lot about your family. For example, from 1930 to 1940 there were 32 less people named Bertelsen in the United States — and some of them are likely related to you.

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What if you had a window into the history of your family? With historical records, you do. From home life to career, records help bring your relatives' experiences into focus. There were 606 people named Bertelsen in the 1930 U.S. Census. In 1940, there were 5% less people named Bertelsen in the United States. What was life like for them?

Picture the past for your ancestors.

In 1940, 574 people named Bertelsen were living in the United States. In a snapshot:

  • 97% rented out rooms to boarders
  • 90 adults were unmarried
  • 142 were children
  • The youngest was less than a year and the oldest was 84

Learn where they came from and where they went.

As Bertelsen families continued to grow, they left more tracks on the map:

  • 95 migrated within the United States from 1935 to 1940
  • Most mothers originated from Denmark
  • They most commonly lived in New York
  • 247 were first-generation Americans