By State law, cities in Kansas are divided into three classes.
Cities of the 3rd Class - When a city incorporates, it becomes a city of the 3rd class. To incorporate, a city must generally have either 300 inhabitants or 300 or more platted lots served by water and sewer lines. (Shawnee incorporated as a city of the 3rd class on June 10, 1922.)
Cities of the 2nd Class - A city may petition to become a city of the 2nd class when its population is more than 2,000 but less than 15,000. A city whose population is between 2,000 and 5,000 may elect to remain a city of the 3rd class, but must become a city of the 2nd class when it reaches 5,000 population. (Shawnee became a city of the 2nd class on January 29, 1957.)
Cities of the 1st Class - A city may petition to become a city of the 1st class when its population reaches 15,000. A city whose population is between 15,000 and 25,000 may elect to remain a city of the 2nd class but must become a city of the 1st class when it reaches 25,000 population. (Shawnee became a city of the 1st class on October 22, 1971).