20 January 1861, the fort on Ship Island, Mississippi was seized by the Confederates; Ship Island was a key base for operations in the Gulf of Mexico and at the mouth of the Mississippi River. In November 1861, the Union occupied the now abandoned fort and held it for the rest of the war. The 9th Connecticut and the 26th Massachusetts were the first of twenty-seven Union infantry regiments to see service on Ship Island during the Civil War. Ship Island had been used as a prison and detention center almost as soon as Union troops landed there. Butler sent the first civilian detainees there from New Orleans in June 1862, a month after he took control of the city. Butler also used Ship Island as a prison for Union soldiers convicted of serious crimes. However, the first Confederate prisoners did not arrive until October 1864, when General E.R.S. Canby ordered more than 1,200 Confederate captives transferred from New Orleans. rochestermilitary.com
