La Crosse is a city in and the county seat of Rush County, Kansas, United States. As of the 2020 census, the population of the city was 1,266. L…La Crosse is a city in and the county seat of Rush County, Kansas, United States. As of the 2020 census, the population of the city was 1,266. La Crosse proclaims itself the "Barbed Wire capital of the world.