Keller is an unincorporated community and census-designated place in southwestern Ferry County in the northeastern part of the U.S. state of Washington. As of the 2010 census, the population was 234. The town is located in the valley of the Sanpoil River, and was founded in 1898 by Baby Ray Peone, a local fisherman. The town was located in the areā¦Keller is an unincorporated community and census-designated place in southwestern Ferry County in the northeastern part of the U.S. state of Washington. As of the 2010 census, the population was 234. The town is located in the valley of the Sanpoil River, and was founded in 1898 by Baby Ray Peone, a local fisherman. The town was located in the area known as "God's Country". At its height the town had an estimated population of 3,500 and even featured a minor league baseball team and red light district. The town was moved several times beginning in 1940 due to backwatering from the Grand Coulee Dam which flooded its previous locations, and is now located 18 miles north of the Columbia River. The series of moves seriously reduced its population over time.