First, the lookout saw the birds.

An army on the move attracts scavengers. Of the winged variety, mainly, which swoop upon whatever scraps are left behind: food, waste and carcasses, both horse and human. Next he saw the dust. And then a vast, dark stain that appeared on the horizon, slowly beetling forward, engulfing everything in sight. An army inhabits, disrupts and destroys the landscape; it is a giant, hungry beast that consumes everything in its path and in most cases – as Salah Al’din was well aware – the mere sight of it was enough to move the enemy to surrender.

Not this time, though. Not when his enemies were the Assassins.

For the campaign the Saracen leader had raised a modest force of ten thousand infantry, cavalry and followers. With them he planned to crush the Assassins, who had already made two attempts on his life and would surely not fail a third time. Intending to take the fight to their door he had brought his army into the An-Nusayriyah mountains and to the Assassins’ nine citadels there.

Messages had reached Masyaf that Salah Al’din’s men had been plundering the countryside, but that none of the forts had fallen. That Salah Al’din was on his way to Masyaf, intent on conquering it and claiming the head of the Assassin leader, Al Mualim.

Salah Al’din was regarded as a temperate and fair-minded leader, but he was as angered by the Assassins as he was unnerved by them. According to reports, his uncle, Shihab Al’din, was advising him to offer a peace agreement. Have the Assassins with them, not against them, was Shihab’s reasoning. But the vengeful Sultan would not be moved, and so it was that his army crawled towards Masyaf on a bright August day in 1176, and a lookout in the citadel’s defensive tower saw the flocks of birds, the great clouds of dust and the black stain on the horizon, and he raised a horn to his lips and sounded the alarm.