Centuries before the invasion, Hyphrates was a lush grassland—which is the reason the initial colonists chose to settle the location. Irresponsible magical excesses, poor agricultural practices, and a number of hideous insect plagues eventually transformed the once fertile land into the largely barren desert that now characterizes the nation. However, the full extend of that change was dramatically accelerated during the early days of the Invasion.
This was when a lesser bureaucrat thought he was using a long-lost ritual to summon the Witch known as the Djinn. Legends indicate that the bureaucrat sought to return Hyphrates to the state of glory it had known in the centuries past. As the nation had become increasingly dependent upon imported goods from Morden's other nations that glory had long lain dormant. When the bureaucrat wished for the Djinn—whom he thought ostensibly under his control through the ritual—to restore that ancient majesty, the Witch chose to carefully interpret that exact wording.
Fully exploiting her powers, as fueled by the permissions granted through the wish, the Djinn chose to restore the majesty of the ancient Hyphrates nation. However, she did so in such a way that they became tools for her use. Ruins of forgotten cities and lost temples emerged from beneath the nation's deserts. The mummified remains of the ancient Hyphrates residents lived anew. Rather than resurrecting the nation and its inhabitants, she restored them to a hideous unlife. While they retained their memories and much of their personalities, the vast majority of these undead were completely under the sway of the Djinn.
The exception to this control was the mummified remains of those burials that had incorporated a particular style of cartouche. When the power of the wish rolled through Hyphrates, these ancient symbols magically reconfigured into Witchmarks. The mummies who bore them were restored to a state of unlife, but with a degree of freedom of thought and personality. Initially, they still had little choice but to obey the Witch's direction, but after the time of her defeat this became far less of an issue. In fact, when the Fey vanquished the Djinn during the Betrayal, all of the members of this Witchbreed gained the ability to act of their own volition.
The only weakness of these undead is the fact that they must take their daily rest within the confines of their ancient sarcophagus. Consequently, the vast majority of Mummies have taken a novel approach to solving this weakness. Rather than having to stay near their tomb and its structure, the mummies have taken to wearing much of their sarcophagus. By constructing joints and straps into its very nature, the statue and coffin-like affair becomes a veritable suit of armor that protects their bandage-enshrouded corpse.
With their minds restored, the Mummies have taken on a variety of different approaches to their new incarnations—and seeming immortality. Some have chosen to view this new chance as an opportunity to make up for past since. It is these who have most frequently joined the Order of the Penitent and joined the fight to overthrow the remaining forces of the Witches. Others believe that this is their due, as they had believed that they were gods in life. It is Mummies of this faction, most of whom have given their allegiance to the false Pharaoh Memmon, who now rule over the Memmon-Aswar portion of Hyphrates. Those who fight against the Witches have been forcibly banished from this land, and are sentenced to dismemberment should they return.