The Black Hawk War began soon after the Sauk Indians, led by Black Hawk, faring poorly in Iowa where the government had moved them, recrossed the Mississippi River and moved back to their former cornfields to plant a new crop. As tensions mounted, panicky settlers killed two Indians seeking a parley and bearing a white flag. Black Hawk, enraged, began killing white settlers.

Sauk followers of Black Hawk were massacred at the mouth of the Bad Axe River in Wisconsin by Illinois militia led by General Henry Atkinson. Old men, women, and children were all killed without regard for pleas of mercy or white flags.

Black Hawk, deserted by his Winnebago allies, surrendered, thus ending the Black Hawk War.