Colony is a city in Anderson County, Kansas, United States. As of the 2020 census, the population of the city was 381. Colony had its start …Colony is a city in Anderson County, Kansas, United States. As of the 2020 census, the population of the city was 381. Colony had its start in the year 1872 by the building of the railroad through that territory. It was named for a colony from Ohio and Indiana, which settled in the neighborhood.