The name Michigan probably means "Great Waters." It is a Native American word. Around 1670, different Jesuit missionaries wrote about a lake called "Machihiganing," "Mitchiganons" and similar names. In 1697 the man who founded Detroit called the lake "Michigan." In the mid-1700s, people began calling the lake between Wisconsin and Michigan "Lake Michigan." In 1784 Thomas Jefferson wanted to call what is now Wisconsin "Michigania," but his bill was never passed. In 1805, the Michigan territory was created. It was named after Lake Michigan.
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