Kansas is a state in the Midwestern United States. Its capital is Topeka and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the west. Kansas is named after the Kansas River, which in turn was named after the Kansa Native Americans who lived along its banks. The tribe's name is often said to mean "people of the wind" although this was probably not the term's original meaning. For thousands of years, what is now Kansas was home to numerous and diverse Native American tribes. Tribes in the eastern part of the state generally lived in villages along the river valleys. Tribes in the western part of the state were semi-nomadic and hunted large herds of bison. The first Euro-American settlement in Kansas occurred in 1827 at Fort Leavenworth. The pace of settlement accelerated in the 1850s, in the midst of political wars over the slavery debate.