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Find more Detlefsen 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 45 more people named Detlefsen 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 222 people named Detlefsen in the 1930 U.S. Census. In 1940, there were 20% more people named Detlefsen in the United States. What was life like for them?

Picture the past for your ancestors.

In 1940, 267 people named Detlefsen were living in the United States. In a snapshot:

  • On average men worked 47 hours a week
  • For 127 females, Minnie was the most common name
  • The youngest was less than a year and the oldest was 102
  • The typical household was 3 people

Learn where they came from and where they went.

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

  • 48 migrated within the United States from 1935 to 1940
  • 50% were first-generation Americans
  • 112 were first-generation Americans
  • Most fathers originated from New York