sentences:  By the late 1700s/early 1800s, Phillipsburg, Hackettstown, Belvidere, and Washington emerged as small settlements and served as the cornerstone communities in lower Sussex County.In 1824, Warren County was established and Belvidere was named as its county seat.As of the 2000 United States Census there were 102,437 people, 38,660 households, and 27,487 families residing in the county.