The land of eastern Kansas consists of a landform known as the Osage Plains. Here limestone cuestas overlook several rivers that drain to the east and south. These rivers include the Verdigris, the Neosho, and the Kansas. The main river between the Kansas to the north and the Neosho to the south and west is known as the Osage in Missouri but in Kansas it has the French name Marais des Cygnes (pronounced "Mair-de-SEEN"), meaning "Marsh of the Swans." Just to the south of the Marais des Cygnes is a smaller tributary known as Mine Creek. Mine Creek merges with the Marais des Cygnes at the Kansas-Missouri border. This region forms the transition between the prairie to the west and woodlands to the east. Prior to white settlement, bluestem prairie covered the higher ground while forests of hickory and oak clustered along the river bottoms. Native animals included deer, antelope, wolves, foxes, turkeys, and even coyotes. The marshy areas also supported flocks of migrating birds.
By the time of European contact, this region was home to two Souian-speaking peoples: the Osage and the Kansa or Kaw. These peoples had in historic times migrated to this region from the east. By the eighteenth century, they had come to dominate the region. Of the two groups, the Osage were concentrated in the southern and central parts of what is today eastern Kansas and western Missouri. One of their major major settlements was along the Little Osage River at what today would be just on the Missouri side of the Kansas-Missouri border. These are the people who the explorer Marquette called "Was-Sah-She," after one of the sub groups. The Osage lived on the edge of the prairies. During the spring, they grew crops in villages along the forest edge. In the summer and fall, they ventured out onto the grasslands to hunt. In the winter, they returned to the forest/prairie border. Anthropologists suggest that in the eighteenth century, the Osage consisted of twenty-four clans equally divided into two major groups: the "Tsi-zhu" or "sky" people and the "Hon-ga" or "earth" people. Clans and groups often had distinct social and ceremonial roles.
Although Spain nominally held the area, the Spanish had little influence in this part of North America. Of the early European explorers, it was the French who in the eighteenth century made the first forays into the region. They were the ones who named the Marais des Cygnes. They were also the ones who made the major trading connections with the Osage and the Kansa bringing with them European trade goods and European diseases. The Osage developed profitable if someone tenuous trading ties to the French, acquiring weapons and metal implements in exchange for furs and slaves, and horses captured from raids. However, even French influence was limited. Other than a handful of forts and trading posts, there were few European settlements this far into the interior of the continent. That would change, however, when the French government under Napoleon Bonaparte sold the land to the United States.