The Pottawatomie River, taking its name from a Native American tribe, has two branches in eastern Kansas. The north fork rises in the southwest corner of Anderson County, about two miles south of the village of Westphalia, and flows in a northerly and northeasterly course.
The south fork rises in Richland Township, also in Anderson County, about two miles west of Selma, and flows northwest into Washington Township, where it turns toward the northeast and forms a junction with the north fork not far from the town of Greeley. From that point, the course of the main stream is northeast until it empties into the Marais des Cygnes River, just below the town of Osawatomie in Miami County. The first white settlers established homesteads near Greeley in the Spring of 1854.