Alton Military Prison

Alton Military Prison

Company type	State penitentiary and military prison
Industry	Corrections, military detention
Founded	1833
Defunct	1865
Headquarters	Alton , United States
Area served	Illinois, United States

The Alton Military Prison, located in Alton, Illinois, was originally founded in 1833 as the state's inaugural penitentiary and ceased operations in 1857. It was reopened in 1862 amidst the American Civil War to function as a Union detention center for Confederate captives until 1865. The structure was dismantled soon after the conflict ended, with only a fragment of the original wall preserved as a historic landmark recognized on the National Register of Historic Places.

Illinois State Penitentiary

Constructed with an initial capacity of twenty-four cells in 1833, the Illinois State Prison in Alton expanded to accommodate 256 cells by the time it closed in 1857, when prison functions were transferred to a new establishment in Joliet, Illinois. This institution incarcerated both male and female offenders; between 1835 and 1858, it held sixty-five women and approximately three thousand men. Female inmates endured severe conditions comparable to those faced by male prisoners, compounded by additional risks. On average, women served less than one year, with nearly half receiving pardons from the governor.

American Civil War prison

During the Civil War, the U.S. government recommissioned the facility in 1862 to detain Confederate prisoners of war. The prison population exceeded 11,000 at times, including notable Confederate officer Ebenezer Magoffin. Mortality rates here surpassed those of other Union prisons due to brutal living conditions and frequent disease outbreaks such as smallpox and rubella. In total, 1,534 Confederate soldiers died within its walls, alongside numerous Union soldiers and civilians.

Historic site

Following its closure in 1865, the Alton prison was demolished except for a remaining portion of its wall. This site was designated on the National Register of Historic Places on December 31, 1974, and later became part of the Christian Hill Historic District in 1978. The State of Illinois currently manages it as a protected historic location.

External links

• Alton Civil War Prison Camp