The bluffs overlooking the Kewaunee River north of the city witnessed much of Kewaunee's early history. Potawatomies had a village there and eventually fought a bloody battle with the Sacs, killing an entire band. French explorers, Jesuit priests, fur trappers, and traders, including Jean Nicolet, LaSalle, and Father Marquette, also stopped there. In the mid-1790s, Jacques Vieau, who later established a trading post at Milwaukee, erected a trading post on the hill north of the river. Kewaunee's "Gold Rush" came in the mid-1830s when gold was supposedly discovered in marshland near the river's mouth. Land speculators such as John Jacob Astor, James Doty, and Joshua Hathaway invested in land, and surveyor Joshua Hathaway laid out plans for a city many believed would rival Chicago. Outrageous prices were paid for swampland before the "gold" was analyzed and found to be iron pyrite, or fools gold. Although the "Gold Rush" ended, investors discovered green gold in the forests that covered most of the area, and as sawmills were established in the 1840s and 1850s, settlers soon rushed to the county.