Tucson began as a fortified trading and supply post during the Great Migration. Migrant families would use Tucson as their final stop before arriving into the Phoenix Valley. The warriors of Tucson were charged with keeping the highway clear of goblin raiders from the northern mountains, along with dispatching the occasional giant or dragon which foolishly wandered too close. Through the decades of migration, a larger settled community grew up around the fort, and Tucson waxed strong as a thriving town.
That idyllic arrangement ended abruptly with the rise of the Dark Hoardes a century ago. Streaming out of the Tombstone region, the undead army swarmed across the desert every evening when darkness fell across the land. Killing all living creatures and smashing to dust any object fashioned by human hands, the Dark Hoardes seemed poised to extinguish the light of the living entirely. The ranks of the undead army were swelled as the corpses of their unfortunate victims were dragged back to Tombstone, thence to be animated with the curse of living death, and sent to join the Dark Army in its assault upon the living remnant.
Smaller settlements were swept away, and even the walls of Tucson were breached. Its citizens panicked as the dead hungry for flesh crawled through the town and over the King's castle ramparts. The noble and ancient clans of the Tucson were perched upon the scarp edge of extermination. But just as the castle walls were falling, and all hope for surivival seemed lost, a great magnificent light broke. The prayers of the faithful were heard, and powerfullly answered.
At the center of town, the walls of the Great Temple were suddenly burning, awash in towering flame. The cadre of temple priests sallied forth from within the temple walls, each of them bathed in a glowing ball of fire, which burned fierce and bright but consumed them not. The undead attackers hissed and groaned frightfully, and were burned into dust wherever they came into contact with the holy fire of the Aryan gods which the priests threw at them. The city rallied, and behind the sacred power of the warrior-priests of Tucson, the Dark Hoardes were for the first time, stymied.
The ensuing battle for Tucson is still the most storied battle in the history of human civilization in Arizona. As every Aryan child learns from birth, the Dark Hoarde, whose ultimate mind and leadership was never determined, seemed to concentrate all of its malign powers against that poor town. In the course of the savage battles that followed, the entire town was overrun and destroyed. Except of course, for the Temple, the one lone human artifice whose holy fires were never extinguished, though seemingly all the underworld was vomited up to snuff it out.
Such malignant creatures which rose up from the underworld in those days, had never been imagined before, whose very existence could scarcely be dreamed of by any but the most insane and depraved mind. Zombie dragons, skeletal giants, armies of goblin ghouls, what hellish creatures were not thrown against those Temple walls? And just as the battle seemed destined for loss, with the Temple's heroic defenders on the verge of complete exhaustion, with the full moon's light blotted out by the rising swarm of vampire bats, whose heart even today can fail to be roused by the arrival of the majestic Phoenix bird that night?
The Arya's long tradition of reverence and friendship for the sacred bird of the central desert was paid in full on that night. Was it motivated to pity by meagre but heartfelt human entreaty? Or was it moved simply by its own distaste for the putrescent swarms of undead impinging upon its desert lands? Perhaps none shall ever know, but the result was spectacular. The night lit up with firestorm, the vampire army, so recently gloating over, even arrogantly toying with their intended victims, suddenly broken, falling back in fear of heat, flame, and holy light. The seige was broken, and Tucson's living remant saved from certain extermination.
The next day, human reinforcements began pouring in to the Temple district from all over the region, and Tucson assumed the mantle that it wears to this day: forward bulwark against the Dark Hoardes of Tombstone. To this day, the warrior-priests of Tucson wage a never-ending battle against the forces of darkness emanating from that evil region.
As of today, the main power of the Dark Hoarde seems to be broken. The highway of the 10 Immortals is still contested ground, leaving our connection to the Great River kingdoms severed. And of course no living being dares approach the district of Tombstone proper. But at least no longer do undead hoardes threaten to overrun the human settlements of the desert lands.