Kissimmee is a city in Osceola County, Florida. It is the county seat of Osceola County. The area was originally named Allendale, after Confederate Major J. H. Allen who operated the first cargo steamboat along the Kissimmee River - the Mary Belle. It was renamed Kissimmee when incorporated as a city in 1883. The name, Kissimmee, came from 'Cacema', a Native American name meaning 'long water'. It’s defined by its proximity to the region’s multitude of amusement parks, including the massive Walt Disney World Resort complex.