Madill is a city in Marshall County, Oklahoma, United States. It is the county seat of Marshall County.The city was founded in 1901 and is named for George Alexander Madill, an attorney for the St. Louis-San Francisco Railway, popularly known as the Frisco. It is best known as the site of the annual National Sand Bass Festival. The population at the 2010 census was 3,770, an increase of 10.8 percent from 3,410 at the 2000 census.
- Madill, Oklahoma on Wikipedia