History in four paragraphs:
First were the Serpentmen, who worshipped terrible Cthonic gods. Their empire was forged in eons before the dawn of history and lasted for millennia. In search for slaves, they bred themselves with giant lizards to produce the hardy Lizardmen, and, for ages, lorded over the Lizardmen masses while constantly honing their blasphemous sorcery. But then, millennia before our time, the great goddess Ixchala revealed herself to a Lizardwoman known only as the Prophetess. With her Lawful divine inspiration, the Prophetess roused the Lizardmen masses in rebellion, shattering their chains of old and overthrowing their masters into oblivion. Freedom was won; and the great Lizard Empire arouse in the jungles, with the Matriarch ruling it with an iron fist from the top of the Great Pyramid in fabled Tollan.
But then came Men, from across the sky, and their arrival upon a shooting star shattered the Lizard Empire. Men also arrived in disarray, and, at first, regressed to savage nomadism, sometimes used as slaves or mercenaries by the Lizardmen city-states which arose from the ashes of the Great Cataclysm. But some Lizardmen and many men, without the guidance of the old Lizard Empire’s Matriarch, turned back to the dead gods of the Serpentmen, and their bloody rituals.
Out of the chaos then rose Sakkara, the great Empire of Man. It grew upon the River of the Desert, worshipping Chaotic gods from beyond the grave and investing their resources in their immortal dead kings much more than in their living subjects. But even great Sakkara, after three thousand years, eventually stagnated and fell back into barbarism, leaving behind ruined temple-yards and ancient tombs filled with gold and peril, as well as the dying city of Zarnas, where the immortal Last Pharaoh rules, in name only, over his ruined empire.
When Sakkara fell, its former vassals to the North, beyond the Great Desert and its River, won their freedom, establishing the new City-States, a mere shadow of Sakkara’s old glory. Some worship the Lawful Gods of Man, while others pay homage to the blood-soaked idols of the long-dead Serpentmen. Meanwhile, the ancient Lizardmen Cities of the tropical South squabble and scheme, some worshipping the Lawful Ixchala, others following the dark Cthonic path of the Serpentmen gods of old.