The Quad Cities is a region of cities (originally four, see History) in the U.S. states of Iowa and Illinois: Davenport and Bettendorf in southeastern Iowa, and Rock Island, Moline and East Moline in northwestern Illinois. These cities are the center of the Quad Cities metropolitan area, which as of 2013 had a population estimate of 383,781 and a Combined Statistical Area (CSA) population of 474,937, making it the 90th-largest CSA in the nation. History Early history Before European settlers came to inhabit the Quad Cities, the confluence of rivers had attracted many varying cultures of indigenous peoples, who used the waterways and riverbanks for their settlements for thousands of years. At the time of European encounter, it was a home and principal trading place of the Sauk and Fox tribes of Native Americans. Saukenuk was the principal village of the Sauk tribe and birthplace of its 19th-century war chief, Black Hawk. In 1832, Sauk chief Keokuk and General Winfield Scott signed a treaty in Davenport after the US defeated the Sauk and their allies in the Black Hawk War. The treaty resulted in the Native Americans ceding of land to the United States in exchange for a much smaller reservation elsewhere. Black Hawk State Historic Site in Rock Island preserves part of historic Saukenuk and is listed on the National Register of Historic Places. The history of urban settlements in the Quad Cities was stimulated by riverboat traffic. For between LeClaire, Iowa, and Rock Island, the Mississippi River flowed across a series of finger-like rock projections protruding from either bank. These rapids were difficult for steamboats to traverse. As demand for river-based transportation increased along the upper Mississippi, the navigability of the river throughout the "Rock Island Rapids" became a greater concern. Over time, a minor industry grew up in the area to meet the steamboats' needs. Boat crews needed rest areas to stop before encountering the rapids, places to hire expert pilots such as Phillip Suiter, who was the first licensed pilot on the upper Mississippi River, to guide the boat through the rocky waters, or, when the water was low, places where goods could be removed and transported by wagon on land past the rapids. Today, the rocks are submerged six feet underwater by a lake formed by two locks and dams. As the Industrial Revolution developed in the United States, many enterprising industrialists looked to the