Milwaukee County is the most populous county in Wisconsin.
According to census.gov, Hennepin County, Minnesota, has the most population at 1,136,599 people.
According to census.gov, Multnomah County, Oregon, has the most population at 701,986 people in 2007.
According to census.gov, Fairfield County, Connecticut, has the most population at 895,015 people in 2007.
According to census.gov, Harris County, Texas, has the most population at 3,935,855 people in 2007.
According to census.gov, Pulaski County, Arkansas, has the most population at 373,911 people in 2007.
According to census.gov, Ada County, Idaho, has the most population at 373,406 people in 2007.
According to census.gov, Middlesex County, Massachusetts has the most population with 1,473,416 people in 2007.
Marion County has the most population In Indiana.
In 2013, which was the most recent time the population of Johnson County Kansas was measured, the population of Johnson County was 559,913 people.
The most populated county in Idaho is Ada County, with a population of more than 390,000.
Greenville County in South Carolina has the highest population.