As of the census of 2010, there were 42,883 people, 16,119 households, and 10,872 families residing in the county.  The population density was 113 people per square mile (44/km²).  There were 17,347 housing units at an average density of 44 per square mile (17/km²).  The racial makeup of the county was 89.8% Race (United States Census), 5.9% Race (United States Census) or Race (United States Census), 0.6% Race (United States Census), 0.4% Race (United States Census), 0.0% Race (United States Census), 1.3% from Race (United States Census), and 1.9% from two or more races.  4.1% of the population were Race (United States Census) or Race (United States Census) of any race. According to Census 2000, 20.3% were of Germans, 18.3% English people, 10.8% Italian people, 10.3% Irish people, 9.4% United States and 7.3% Polish people ancestry and 96.0% spoke English language and 3.0% Spanish language as their first language.. Which ancestry group had the least amount of people in the population?