Peabody is a city in Marion County, Kansas, United States. It is named after F.H. Peabody, of Boston, former vice-president of the Atchison, Topeka and Santa Fe Railway. Peabody is well known in the region for its Independence Day Celebration on July 4, and its historic 1880s downtown main street. As of the 2010 census, the city population was 1,210, a decline from 1,384 in 2000.