Sumner is a city in Chariton County, Missouri, United States. The population was 78 at the 2020 census. It was named in praise of U.S. Senator Charles Sumner.

The area along the Grand River in the northwest corner of present-day Chariton County was first explored by two sons of Daniel Boone and Thomas Stanley prior to Missouri statehood in 1821. Stanley customary a trading reveal some period later near what would eventually become Sumner. Other than the trading post not much existed in the area for several years, partly due to marshlands and flooding upon the Grand River. The area around Sumner was originally known as Crossland, and about one mile away was the much larger village of Cunningham. However the coming of the Chicago, Burlington and Quincy Railroad to the community combined taking into consideration the Wabash railroad’s decision to concern their depot from Cunningham to Sumner gave the latter the upper hand in growth. Sumner was laid out by Joel H. Wilkerson in June, 1882. That fall the first home was constructed in the other village by J.M. Vanes, soon followed by the Commercial Hotel. A newspaper, the Sumner Star, was received in 1890 and operated for several years. Once teeming later wildlife such as prairie chicken, turkey, duck, and deer in the 1800s, the population of such was drastically reduced by beyond hunting and draining of the native wetlands, notably Hog Lake in 1911. In 1937 concerned over wetland preservation in the wake of the Dust Bowl, the U.S. Congress acknowledged the Swan Lake National Wildlife Refuge just to the south of Sumner. Roads, buildings and man-made wetlands were soon created by the Civilian Conservation Corps and by 1941 eight hundred geese wintered in the area.

Located on a migratory flyway, Swan Lake and the Sumner area began to attract ever larger numbers of geese in the mid and late 20th century, reaching 100,000 or more by the 1980s and 1990s. This after that led to a once a year influx of hunters, benefiting the few Sumner businesses and Chariton County as a whole. With these numbers in mind Sumner was proclaimed the “Wild Goose Capital of the World”. Sumner then began to preserve a twelve-monthly Goose Festival in 1955 and it continues each October, with a variety of undertakings held including live music, a queen contest, food and a parade. Sumner residents commissioned a Kansas City sculptor in 1976 to Make a large statue to award the community’s status and reputation for waterfowl hunting. What resulted was the “Worlds Largest Goose”. Named “Maxie”, the fiberglass and metal structure stands over forty feet tall with a wingspan of sixty-five feet and a total weight of over 5,000 pounds.

Sumner is located at 39°39′23″N 93°14′36″W / 39.65639°N 93.24333°W / 39.65639; -93.24333 (39.656342, -93.243426).