The creation of the Felinis
It was a warm evening, as most evenings were at the Nile valley. Ramses Mau III was sitting on top of the small temple watching the sunset and licking his paws. After finishing his cleaning ritual he jumped down the steps, planning to go down to the fishing village and maybe steal some little fish from the fisherman. Just as he was passing in front of the temple door, something caught his attention. There was a funny smell coming out of the small temple and a soft purple glow was lighting up the walls. This needed to be investigated, so Ramses went in. In the small inner chamber was the High Priest, the same one that had kicked him 3 years ago and who still received a daily dose of piss-in-shoes for that horrible trespass. In front of him on the floor, there was a big red circle with numerous funny characters written on its outer edge. What really caught Ramses' attention though was within the circle, or rather above it.
Fifty centimeters above the ground at the center of the circle something was... levitating. It seemed alive and it would have passed for an animal, as it had the correct number of limbs, eyes, and ears, only they were all in the wrong places. It had a mouth though and from this mouth, a chant came out in unison with the humming coming from the High Priest. As Ramses stood there watching the chanting grew louder and faster and the light coming out of the thing's mouth grew brighter. Ramses wasn't one for action but at that instant, he had the unmistakable instinct to kill. And he always followed his instincts. As the chanting grew to a pitch so high it was painful to listen to he leaped through the air, his talons out, fangs ready to bite, at the same instant as a purple lighting bolt jumped from the levitating mass to the Priest's staff. The rest was a quick blur of lightning fangs, claws, screams, and a lot of blood. When Ramses came back to his senses several hours later he didn't remember much of the fight. But he had a sudden feeling of clarity, something he had never felt before.
There is some possibility that this is what happened. At least that's Ramses' version of it. There are, of course, other versions, some including a clumsy cat falling inside a cauldron which was at the time being used to boil a potion infused with elder magic. Whatever the exact situation was the result is the same - at that instant, Ramses Mau II seized being a normal cat and became a Felini - a cat with intellect rivaling that of humans and the power to channel the magic of the elder gods. One particular manifestation of that power was the ability to hypnotize humans with lower willpower and turn them into mindless slaves, creatures whose only purpose is to serve their Felini masters, and who call themselves "cat-people". Using his newfound powers Ramses quickly set about enslaving everyone he could lay his eyes on. His conquest was unfortunately cut short when he encountered the High Priest and found out that not only did his hypnotism not work on the man but that there are others much more adept at the use of elder magic than he himself is.
Ramses was lucky though because at that time cats were revered as sacred in Egypt, so instead of killing him, the priests just entombed him in a pyramid buried under the timeless sands of the Sahara desert.
This would have been the end of the Felini race if some pesky archeologists didn't excavate the tomb some 10,000 years later. By that time nobody remembered that there are cats who can wield elder magic and enslaved humans, so the main emotions when they saw Ramses emerge from the tomb, were a mixture of pity, and some disgust (nobody had seen a hairless cat for some millennia). The archaeologists were promptly enslaved, and those who couldn't be enslaved were promptly executed. In the ten millennia he has spent underground Ramses had learned a trick or two on how to use his newfound powers and several unlucky archaeologists found themselves locked in the same dimension as a thousand elder gods. Not a pretty place to be in, even if you ignore the smell of rotten eggs.
On top of being able to open portals to the nether realm (or whatever people call it), Ramses had also developed the ability to turn other normal cats into Felinis. All of this meant that the whole planet was soon overrun by the newly developing race. Now, this was before humans had met the Mushroom people, so they still didn't have FTL communication or engines. Therefore, it took the Human Federation almost a year to react to the news and send death squads armed with catnip, laser rifles, and tactical nukes to eradicate the cats. By the time this happened several hundred ships filled with the Felinis and their human slaves had escaped the planet and fled far away in the galaxy.