Kenedy County is a county located in the U.S. state of Texas. As of the 2010 census, its population was 416. It is the third-least populous county in Texas and fourth-least populous in the United States. Its county seat is Sarita. The county was created in 1921 from parts of Hidalgo and Willacy counties and is named for Mifflin Kenedy, an early area rancher and steamboat operator.