Shawnee's fur trading and pioneering heritage blends histories of these Kansas Territory townships: Monticello and Shawnee. Additionally, the Kempf Family Homestead and Dairy is a major source of local produce and works with local schools to encourage agricultural growth in the area.
According to the United States Census Bureau, the city has a total area of 42.5 square miles (110.2 km²), of which, 41.7 square miles (108.1 km²) of it is land and 0.8 square miles (2.1 km²) of it (1.88%) is water.
There were 18,522 households out of which 36.3% had children under the age of 18 living with them, 60.3% were married couples living together, 8.2% had a female householder with no husband present, and 28.5% were non-families. 22.7% of all households were made up of individuals and 5.2% had someone living alone who was 65 years of age or older. The average household size was 2.58 and the average family size was 3.07.
In the city the population was spread out with 26.8% under the age of 18, 7.8% from 18 to 24, 34.2% from 25 to 44, 22.7% from 45 to 64, and 8.5% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 96.9 males. For every 100 females age 18 and over, there were 94.7 males.
The median income for a household in the city was $59,626, and the median income for a family was $70,288. Males had a median income of $45,777 versus $31,428 for females. The per capita income for the city was $28,142. About 2.2% of families and 3.3% of the population were below the poverty line, including 2.9% of those under age 18 and 4.0% of those age 65 or over.