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Find more Koski 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 493 less people named Koski in the United States — and some of them are likely related to you.

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Create, build, and explore your family tree.

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 3,263 people named Koski in the 1930 U.S. Census. In 1940, there were 15% less people named Koski in the United States. What was life like for them?

Picture the past for your ancestors.

In 1940, 2,770 people named Koski were living in the United States. In a snapshot:

  • 43%, or 301 people, lived in homes they rented
  • 720 adults were unmarried
  • 4% were disabled
  • 367 owned their homes, valued on average at $2,162

Learn where they came from and where they went.

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

  • 1,256 were born in foreign countries
  • Most mothers originated from Michigan
  • The most common mother tongue was Polish
  • 1,777 were first-generation Americans