The Political Graveyard: Marshall County, Oklahoma - Database provides political history, cemetery locations, and brief biographies of politicians who were born or lived in the county. - http://politicalgraveyard.com/geo/OK/MS.html#CEM
Marshall County Demographics - Provides report from the U.S. Bureau of the Census, Census 2000. [PDF file] - http://staging.okcommerce.gov/test1/dmdocuments/Marshall_County_Demographics_061004324.pdf