Complex sentence: Marshall was a political and production center of the Confederacy during the Civil War and was a major railroad center of the T&P Railroad from the late 19th century until the mid- 20th century.
Split into simpler sentences: Marshall was a political and production center of the Confederacy during the Civil War. Later it was a major railroad center of the T&P Railroad from the late 19th century until the mid- 20th century.