The Immotal 600 were, I believe, all officers, and were taken from Fort Delaware, and placed on Morris Island next to Federal artillery batteries which were then firing on civilain targets in the city of Charleston. Those batteries therefore came under Confederate counter-battery fire. By placing the prisoners adjacent to the guns, the purpose was to suppress the counter battery fire. It did not work. After outrage even in the Northern press they were eventually removed to Fort Pulaski, where they were held for several months. But their designation as the Immortal 600 came from being held under fire on Morris Island, not at Fort Pulaski. Conbditions at Fort Pulaski were not ideal; they were imprisoneed in unheated casements of the fort on the river, where many did fall ill. But conditions there were more healthful than at Fort Delaware, and certain better than such prison pens as Point Lookout, Elmira, Camnp Chase, Camp Douglas, and Rock Island.

MGEN Benjamin F. Butler did much the same thing with mostly enlisted Confederate prisoners, making them work on the construction of the Dutch Gap canal on the James River below Richmond. The Confederates had been shelling the USCT's who were digging the canal, so Butler placed the Confederates under fire with the expectation that the shelling of his troops would stop. In both cases the Federals were essentially using the prisoners of war as human shields, a practice that is expressly forbidden by the present International Laws of War. But anyone whith a shred of decency understood at the time that the practice was morally reprehensible.