According to census.gov, Garfield County, Washington, has the least population at 2,050 people in 2007.
As of the 2000 Census, the population of Washington County Idaho is, 9,977.
According to census.gov, Calhoun County, Arkansas, has the least population at 5,535 people in 2007.
According to census.gov, Arthur County, Nebraska, has the least population at 356 people 2007.
Kent County with a population of 19,197.
According to census.gov, King County, Washington, has a population of 1,826,732.
According to census.gov, the 2007 ACS population estimate for Pierce County, Washington, is 773,165.
According to census.gov, Jones County, South Dakota, has the least population at 1,055 people in 2007.
According to census.gov, King County, Washington, has the most population at 1,859,284 people in 2007.According to "Washington State" history book: King County with 1,685,600 as of 2000.
Highland County
The largest county by population is King. The largest in size is Okanogan, 5,268 square miles.
Petroleum County is the least populated county in Montana, with a population of around 500 people.
County Leitrim has the smallest population in Ireland.