Mahlon Dickerson Manson spent his first years near Piqua, Ohio, where he was born in 1820. When Mahlon was twelve his family moved to Indiana. After studying pharmacy Manson opened a drug store in Crawfordsville. He left Indiana to serve in the Mexican War but returned to Crawfordsville and his business.
Named for a former governor of New Jersey, Manson seemed destined to enter politics. In 1851 he ran as a Democrat and won a seat in the state legislature. It was the beginning of a lifelong career. Mahlon Manson served in elected offices or held political appointments until his death in 1895.
The Civil War
In 1861 Manson helped raise the 10th Indiana Infantry. He fought with the 10th at Rich Mountain, West Virginia. As commander of the regiment at the Battle of Mill Springs, Kentucky, he earned the rank of brigadier general. His regiment took part in the siege of Corinth, Mississippi in May 1862. That summer Manson was sent to Kentucky to help defend the state against a Confederate invasion.
In Gen. William Nelson's absence, Manson commanded the Union army at Richmond. Like many of his men, Manson was captured. After he was exchanged, Manson commanded a brigade in the Knoxville and East Tennessee campaigns and led an infantry column pursuing Confederate Gen. John Hunt Morgan in Ohio. After being severely wounded at the Battle of Resaca in May 1864, during the Atlanta campaign, he spent 85 days in the hospital. In December 1864 he resigned his commission and resumed his life in politics.