Whitman County /

Whitman County is a county located in the U.S. state of Washington. As of the 2010 census, the population was 44,776, with the majority living in its largest city, Pullman, home to Washington State University, the state's land-grant university. The county seat is at Colfax. Whitman County was formed out of Stevens County on November 29, 1871. It is named after Marcus Whitman, a Presbyterian missionary who, with his wife Narcissa, was killed in 1847 by members of the Cayuse tribe. According to the U.S. Census Bureau, the county has a total area of 2,178 square miles (5,640 km²), of which 2,159 square miles (5,593 km²) is land and 18 square miles (47 km²) (0.84%) is water. Whitman County is part of the Palouse, a wide and rolling prairie-like region of the middle Columbia basin. Rivers Lakes and reservoirs Summits and peaks Notable parks As of the census of 2000, there were 40,740 people, 15,257 households, and 8,055 families residing in the county. The population density was 19 people per square mile (7/km²). There were 16,676 housing units at an average density of 8 per square mile (3/km²). The racial makeup of the county was 88.07% White, 1.53% Black or African American, 0.73%