One of the wealthiest men, John Jacob Astor, based his company, the American Fur Trading Company, in Mackinaw Island, Michigan.

FORBES: Was I Wrong About Michigan?

He was a great-great-grandson of real estate and fur magnate John Jacob Astor, one of the United States' first multimillionaires.

WSJ: Astor son, 88, loses appeal, could face prison

Ms. Astor, the widow of a descendant of 19th-century magnate John Jacob Astor, died in 2007 at the age of 105.

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Swelling demand pushed trappers farther west, cutting new trade routes, expanding a young nation's borders and creating the first American multimillionaire, John Jacob Astor.

FORBES: Magazine Article

In the 1830s, John Jacob Astor transferred his fortune in beaver pelts and international trade into real estate, to become New York's largest landholder and richest man.

WSJ: The Greatest Grid | Museum of the City of New York | Crosshatching a Miracle | By Ada Louise Huxtable

John Jacob Astor, flogging his furs, might not have approved.

ECONOMIST: David Astor | The