Fort Mackinac on Mackinac Island was constructed in 1779 in order to protect the lucrative fur trade in northern Michigan and maintain relations with neighboring Native American tribes. The military importance of the Fort diminished as the nineteenth century progressed, but the Fort took on a new role when the Mackinac National Park was established in 1875. The soldiers continued to train during this time, but their main duties now entailed caring for the Park. In fact, the Fort itself became a tourist destination, and people gathered to watch the military exercises of the soldiers.
Since the Fort saw little military activity, the soldiers had lots of extra time on their hands, which naturally led to some of them getting into trouble. Soldiers who committed crimes of drunkenness, petty theft, insubordination, and desertion were thrown into the prison cell in the Guardhouse.
Conditions in the Guardhouse prison cell were miserable. The single room was dark, unheated, unventilated, and lacked furnishings. Prisoners had to sleep on the floor and were denied use of the Fort’s state-of-the-art restroom facilities. The rations of the soldiers were also greatly reduced. Once, as many as thirteen prisoners filled the prison cell at one time. Only in the 1880’s were a small window, an air shaft, a coal stove, and a sleeping platform added to improve conditions.
In the 1930’s, workmen discovered “The Black Hole,” which dated back to the beginning of the Fort and had remained hidden beneath the floors of the Guardhouse. The Black Hole consisted merely of a hole in the ground with stone walls and a dirt floor. Little light and air entered it, and in 1800 one prisoner died in its suffocating conditions. The Black Hole served as the prison cell for the Fort until the present guardhouse was constructed in 1828.
In addition to time in the prison cell, soldiers could be whipped with a Cat-O-Nine-Tails in front of assembled troops, forced to perform hard labor in leg irons attached to a ball and chain, and suffer a reduction in pay.