Pasco County is a county located in the U.S. state of Florida. Its county seat is Dade City. It is on the list of the 100 fastest growing counties in the country. Pasco County was created in 1887 and named for Samuel Pasco, who served in the Confederate Army, the state legislature and in the US Senate from 1887 to 1899. Pasco County has a total area of approximately 868 square miles of which 85% is land and 15% water. As of the 2000 census, there were 344,765 people, 147,566 households, and 99,016 families residing in Pasco County, FL.