10 billion years ago give or take a billion

The first dawning of intelligence happened, in the farthest corner of the Universe. They reached the pinnacle of Magic and science long before the Milky Way Galaxy formed. They realized that their kind of life would not survive forever, as the universe grew older and new types of stars and galaxies were being born, theirs were a type of life that was limited. But they also knew they did not have to truly die out.

They created a plan, it was a simple plan, seed every galaxy every world with their DNA, seed this reality with their life essence, and they will not truly die. They made space probes that could self-replicate and seed worlds with DNA. These probes seeded the universe over the course of the next 5 to 6 billion years, eventually one of their ancestor races adjusted the programming to ensure that all life would eventually form into humanoid life. These modified probes seeded all the worlds in the Milky Way. The first races to reach space around 66 million years ago were humanoid reptiles who wear called the Dragons and the Humans called Atlanteans, they had a short war, the Atlanteans won, destroying the world the Reptile humanoids came from. This event Humans of Earth would one day call the Cretaceous–Paleogene extinction event which killed the Dinosaurs.

Atlanteans eventually had a Galactic Empire, the Milky Way was called The Atlantean Star Empire, although the Atlanteans did not have slavery or a concept of slavery, they had a rigid class system. The Royal Atlanteans which were dark-skinned humans with silver-blonde hair and Purple eyes ruled all intelligent life in the Galaxy. Under them were the Normal Atlanteans who had dark skin with dark hair and green eyes, if you have ever seen a North West African, you have seen an Atlantean. This included lower Atlanteans, which also can be called just Humans, these Humans came in all sizes shapes and colors as well, but dark skin was considered a sign of wealth, since in an intergalactic civilization, getting sunlight was a luxury, so workers and the poor tended to become pale as they needed less solar protection than the rich who could laze outside on the surface of worlds. Under the Humans were the humanoids, they came in all sizes and shapes, everything from Dwarves, Elves, and Giants. These races came from the various conquered worlds. They usually ended up as menial labor, which involved tedious and boring tasks since machines did all true labor including food production.

Some of the unique races that also existed wear the demi-humanoids, these were races based on Atlantean DNA mixed with animals for specialized purposes, such as Cat and Dog people, these people were the only slaves in their civilization, as they were created for specific jobs ie warriors, and domestic security. They were however not treated like slaves, even if they had no say in what they did with their lives.

During this golden age of Atlantean civilization, the dragons plotted and caused an uprising against the Atlanteans from the shadows. This civil war was quick, and the lower classes lost the war, as the Atlanteans created a new race of Warriors the Angels, the Angels defeated the uprising and took the prisoners of war to a penal world, the Earth. This was around 120,000 years ago.

The dragons, however, were not done with trying to gain revenge, the reptilian humanoids faced the Atlanteans in secret wars for eons, and their science and magic was on par the Atlanteans. They developed two methods to fight the Angels, the first were Vampires, using their nanotechnology implanted in humanoids they could give great powers, and the second was the development of the Demon Race. Using captured Angels, they mutated their DNA, to make a new race of Humanoids that could face off equally to the Angels. The differences between the Angels and the Demons were minor, they were always born Female, and their growth throughout their lives they would shift between male and female forms, they had wings which could be hidden White feathered wings for Angels, and Black Feathered or Dragon wings for demons. Both races are capable of flight, they had Horns, yes Angels have horns, although theirs form into the Halo shape, while Demon horns are shaped like Dragon Horns. Although Angels and Demons can produce fertile offspring,  they can not breed with humans, not without using magic and science, and then the child is an infertile hybrid called a Nephilim. There are few Nephilim, as they are extremely hard to produce, and they are not so great at magic.

Around 15k years ago the Atlanteans set up a resort city on the Earth in the North West corner of Africa. This was a royal retreat, used by the children of the Royal family, it was a pinnacle city of Atlantean technology and magic. They also refused contact with the much more primitive societies of the penal colonists, who were now tribal and without any science or technology, and only the most basic concepts of magic.

Around 12k years ago, using Demons and Vampire warriors, the Dragons who now called themselves Titans, faced the Atlanteans in a massive Galactic war. This war collapsed galactic civilization, Most of the Royal Atlanteans and most of the Titans fell by the end of the war, Galactic peace was achieved by the collapse of all civilization. Strangely this allowed Earth to develop more or less free of influence. As few traveled in space. However not every race was happy in this peace even if the Dragons and the Atlanteans could find peace and coexist their creations the Angels and Demons refused to stop fighting each other until around 1300ce when the remaining Demons and Angels still with interstellar starships met over the Earth and faced off in a battle to end their personal war. That battle ended with the near-total destruction of all forces, Demons and Angels lost all their starships, and the last ships with manufacturing capabilities. The survivors crashed on the Earth and chose to use magic to hide their presence. Eventually, Demons and Angels made peace, as there was no point in them fighting anymore.

 Rules of peace agreed to by the Leaders of the Angels and Demons of Earth.

1. All angels and demon children shall be raised as a human.
2. All angels and demons must hide as humans and cannot allow their children to learn their true nature until they are 18.
3. Angels and Demons shall not create Nephilim. But they are allowed to have relationships with humans.
4. The only humans allowed to know the truth must be in a relationship with the Angel or Demon.
5. If an angel or demon child learns the truth before their 18^th birthday their gender shall be reset, and their memories altered the memories of all humans shall be adjusted to match as well.    
6. Angel and Demon ranks and hierarchy shall be merged, and the ranks and privileges shall be respected.

Ok Info dump done with cheap book from the 1950's. I need art for this, it would be funnier that way. Maybe once the Story is at the end, and I go back to redo it, make it longer and add details, I'll do the art or get an artist to do it. I can just imagine what 1950's space demons and angels would look like. If done to look friendly.