As of the 2000 census, there were 606,024 people, 224,852 households, and 157,846 families residing in the county. The population density was 290 people per square mile (112/km2). There were 236,205 housing units at an average density of 113 per square mile (44/km2). The racial makeup of the county was 85.63% White, 1.67% Black or African American, 1.36% Native American, 5.78% Asian, 0.28% Pacific Islander, 1.92% from other races, and 3.36% from two or more races. 4.72% of the population were Hispanic or Latino of any race. 16.2% were of German, 10.0% English, 8.8% Irish, 8.4% Norwegian and 6.6% United States or American ancestry.