Humans have inhabited what is now Missouri for over 12,000 years. The Mississippian Culture that flourished beginning in approximately the 9th century and created cities and mounds, began to decline in the 14th century. French missionaries and fur traders, arriving in the late 1600s, encountered the Osage Nation in the southwest, the Missouria Nation in the northwest, and the Illini Nation in the east.
Frenchmen founded St. Genevieve in 1735 and St. Louis in 1764, settling mostly in towns to the south on the Mississippi River. After a brief period of Spanish rule, the United States bought the Missouri territory from France as part of the Louisiana Purchase in 1803. There were still a few thousand French settlers in the area, but most of those who followed were of English or Scots origin who had arrived by ship and had first settled in Tennessee, Kentucky, or elsewhere in the Southeast United States.
Missouri played a central role in the westward expansion of the United States, as memorialized by the Gateway Arch in St. Louis. The Pony Express, Oregon Trail, Santa Fe Trail and California Trail all began in Missouri.
In the early years, slaves were brought to the Missouri territory to work in lead mines and on farms, and on the Mississippi riverboats and ferries. Missouri entered the Union as a slave state in 1821 as part of the Missouri Compromise.
After the Civil War, freed slaves came north looking for work, and during the Great Migration, 1916 to 1970, over six million African Americans from rural areas of the South moved to urban areas in the Northern and Western states, including Missouri.
Immigration from overseas swelled in the 1830s when large numbers of Germans began to settle the farm country west of St. Louis and south of the Missouri River in an area known as the “Missouri Rhineland.” Beginning in the 1840s, both German and Irish immigrants settled in the larger urban centers as well.
Before rail travel was widely available, the Ohio-Mississippi-Missouri river system was a major means of transport to Missouri. After 1869, when the transcontinental railroad was completed, immigrants entering the US on the East Coast were more easily able to reach Missouri. In the 1880s, St. Louis and Kansas City attracted Italians, Greeks, Poles, and other eastern Europeans. In the 20th century, people from many parts of the world, including Hispanics, Asians, and Africans came and made Missouri their home.