The siege strategy, however, scuttled a secret plan the Quraysh were counting on. After the disastrous battle of Uhud, another of Medina’s Jewish tribes had been exposed as collaborating with the Meccans. Like the first Jewish tribe, they had been tried and sent into exile. The third tribe, the Banu Qurayza, then proclaimed its loyalty to the Pact of Medina. Now, however, in the run-up to the Battle of the Moat, its leaders had secretly conspired with the Quraysh to fall upon the Muslim forces from behind as soon as the Meccan forces attacked from the front.
