He was Mayor of Baltimore temporarily during the American Civil War for 28 days, from September to October 1861.
[1] In 1830, Blackburn ran for the office of judge of the Baltimore County Criminal Court.
[2][3][4][5] Blackburn succeeded George William Brown as ex officio Mayor of Baltimore on September 21, 1861 when Mayor Brown was arrested by federal authorities and imprisoned in Fort McHenry during the American Civil War.
He succeeded Brown due to his role as president of the First Branch of City Council.
Historians did not know about his successor, another temporary mayor during the Civil War, Charles J. Baker, until 1989.