Pierce county is located in northern North Dakota and calls Rugby its county seat. The county population on July 1, 1999, was 4,594, a decrease of 458 over the 1990 census.

The inverted "L"-shaped county is situated in the Lakes and Gardens Region and sports several pothole lakes, including Round, Spring and Grass Lakes, to the north and Red, Kilgore and Antelope Lakes (among others) to the south. In addition, it shares Smoky Lake with McHenry County and Long Lake (not to confused with the larger Long Lake in the southern part of the state) with Benson County.