On July 29, 1864, Major-General John Foster sent his Aide-de Camp Major John Anderson forward under a flag of truce to Confederate lines near Port Royal Sound. Anderson carried this message:
Maj. Gen. Samuel Jones,
Comdg. Confederate Forces, Dept. of S.C., Ga., and Fla.:
General: I have the honor to inform you that the Secretary of War has authorized me to exchange any prisoners in my hands, rank for rank, or their equivalents; such exchange being a special one. In accordance with the above I send Major Anderson to make arrangements as to time and place for the exchange.
I have the honor to be, very respectfully, your obedient servant,
J. G. Foster,
This set in motion the exchange of fifty Confederate officers, who had just arrived at Morris Island, as their stockades had to be prepared, for fifty Federal officers, who had been held in Charleston, subjected to Federal artillery fire, since June.
The exchange itself, which I’ll discuss at the appropriate 150th interval, was pretty typical for a prisoner exchange. But the actual exchange itself sent mixed messages. Foster’s words, which echoed his instructions from Washington, pointed out this was a special arrangement and one-time deal. On the Confederate side, Jones and others read into this. More prisoner exchanges, small or large, would work to benefit the Confederacy at several levels. So why not more? And that was part of Jones’ motivation to bring 600 Federal prisoners to Charleston… in hope of a similar, but larger, exchange.
(Citation from OR, Series I, Volume 35, Part II, Serial 66, page 198.)