It is located approximately 30 miles (48 km) east of Kansas City.

[5] According to the United States Census Bureau, the city has a total area of 1.75 square miles (4.53 km2), all land.

[6] Napoleon lies just a few miles west of Wellington, the two towns having been named after the commanders at the Battle of Waterloo.

Approximately halfway between the two towns lies a small, unincorporated crossroads called "Waterloo".

Napoleon is located in the northwestern corner of Lafayette County and bordered on the north side by the Missouri River and on the south side by U.S. Route 24 and on the west by Jackson County.

15.3% of all households were made up of individuals, and 5.9% had someone living alone who was 65 years of age or older.

The racial makeup of the city was 94.71% White, 1.92% African American, 0.48% Asian, and 2.88% from two or more races.