Memphis is a city in Shelby County, Tennessee, United States, and its county seat. Situated along the Mississippi River, it had a population …Memphis is a city in Shelby County, Tennessee, United States, and its county seat. Situated along the Mississippi River, it had a population of 633,104 at the 2020 census, making it the second-most populous city in Tennessee, the fifth-most populous in the Southeast, and the 28th-most populous in the nation. Memphis is the largest city proper on the Mississippi River and anchors the Memphis metropolitan area that includes parts of Arkansas and Mississippi, the 45th-most populous metropolitan area in the U.S. with 1.34 million residents.