Harris County is a
county located in the
U.S. state of
Texas. As of the
2010 census, the population was 4,092,459, making it the most populous county in Texas and the
third-most populous county in the United States. Its
county seat is
Houston, the largest city in Texas and fourth-largest city in the United States. The county was founded in 1836 and organized in 1837. It is named for John Richardson Harris, an early settler of the area.