From what three countries were most of the continental United States a part of?

Brazil is the only country that is larger in total area than the contiguous United States, but smaller than the entire United States, while Russia, and Canada, and China are the only three countries larger than both.

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List of contiguous U. S. states:

Texas.

Utah.

Vermont.

Virginia.

Washington.

West Virginia.

Wisconsin.

Wyoming.

I hope this proves useful!