Pity the doomed Confederate leader Lt. Gen. John C. Pemberton. Nearly a century and a half ago he and his embattled men waited for an encoded message to arrive detailing their reinforcements. Unfortunately for him, the message arrived in 2010.
Not that it would have mattered. You see, Pemberton was waiting for a message explaining that his commanding officer, General Joseph E. Johnston, across the Mississippi River at the time, had no men or ammo to spare for the forces hunkered down in Vicksburg. Nevertheless, the Confederacy saw fit to send a nice, encoded message to the doomed Lt. General anyway.
Pemberton's loss was historians gain however, as some 147 years after the paper message was corked in a vial it was examined, opened and decoded.
It took two weeks of manual cracking (no computers were used), after which retired CIA code breaker David Gaddy had an answer (as relayed to the Associated Press by Museum of the Confederacy collections manager Catherine M. Wright). Once broken, the simple "Vigenere cipher" used by the Confederacy gave up the goods:
"He's saying, 'I can't help you. I have no troops, I have no supplies, I have no way to get over there,' " [Wright] said of the author of the dispiriting message. "It was just another punctuation mark to just how desperate and dire everything was."
Indeed, the situation surrounding Pemberton in Vicksburg was dire. When Union General Ulysses S. Grant encircled the city in 1863, its citizens were forced to eat dogs, cats and soup made from wallpaper paste. When the battle was ended, Vicksburg refused to celebrate July 4 for the next 80 years! [AP - Thanks, Sebastien]