Benton Township is one of eleven townships in Monroe County, Indiana, United States. As of the 2010 census, its population was 3,358 and it contained 1,716 housing units. Benton Township was established in 1833. It was named for Thomas Hart Benton, a U.S. Senator from Missouri. Benton township was divided into Marion township to the north and B…Benton Township is one of eleven townships in Monroe County, Indiana, United States. As of the 2010 census, its population was 3,358 and it contained 1,716 housing units. Benton Township was established in 1833. It was named for Thomas Hart Benton, a U.S. Senator from Missouri. Benton township was divided into Marion township to the north and Benton township to the south in August 1845. The current township was formed in January 1916 when Marion township and Benton township merged back together to form a single township.