The low rolling hills of Marion County have been cleared of trees, and the area is completely devoted to municipal development or to agriculture, except for wooded drainages.

[3] The highest point (920 feet/280 meters ASL) is a small ridge at the county's northwest corner.

Marion County was created on April 1, 1822, from part of the "New Purchase" lands that had been obtained from its inhabitants, the Lenape, by the Treaty of St.

[8] It is named for Francis Marion, a brigadier general from South Carolina in the American Revolutionary War.

The northern two-thirds of Marion County is in Indiana's 7th congressional district, which is held by Democrat André Carson.

Indiana's 6th congressional district, which runs along the southern third of the county, is held by Republican Greg Pence.

In the State Senate Marion County is divided among nine districts, which are held by two Democrats and seven Republicans.

Between 1896 and 2000, it went Democratic only four times, in the national landslides of 1932, 1936 and 1964 as well as 1912 when Woodrow Wilson won a plurality in the county.

The Republican edge began to lessen considerably in the 1990s, and in 2004 John Kerry became the first Democrat since Lyndon B. Johnson in 1964 to carry the county.

The trend continued in 2008 and 2012 with Barack Obama showing strongly in Marion County, winning 63% and 60% of the vote respectively.