I'm working on a sci-fi world called Sorka, but I plan on creating the history from the creation of it thousands or even millions of years before the events of my story take place. I've already done the creation myth by the goddess Aya and how humans were put on the world by her. My problem is getting the world taken over by one of the five ancient civilizations. I planned on them having what they call the Never-Ending War, an extremely long conflict that, at the time, never looked like it was going to end. These are the five tribes, similar to that of Nordic or Germanic tribes. (note: B.D. is an acronym for Before Do'on, a mortal sent by Aya to save the planet) The Repnian Tribe and Repna The first Temple of Aya was built by the Repnians in 3015 B.D. out of an element only found on Sorka called Ayalium. It was white, like marble, but was virtually indestructible. It had a shiny aura to it, which made it even more beautiful and demanded. It was used as the main building material in the Repnian settlement until it's shortage in 2662 B.D. In between the years, the Repnians built many great structures from such as great stadiums, religious structures dedicated to Aya, record buildings, and many fountains to symbolize Aya's. When there was the shortage, the Repnian tribal leaders agreed to only use Ayalium on special occasions on which they would vote for. They founded the city of Repna. Repna is the oldest and biggest city on Sorka. It is on an island in Lake Repna at the end of the Repnian River. It also surrounds the lake shore. The Temple of Aya is at the exact center of the island. The tribe was very sophisticated, but very smart in war tactics and knew how to defend their land with pride. They were very individualistic and only noblemen and women had freedom. The Hi'alian Tribe and Hi'al This tribe first appeared in 3027 B.D. This tribe is most famous for trading with the Repnian and creating a predecessor of the Sorkan alphabet. They created the modern city of Hi'al. They were a peaceful tribe and elected to have a limited military force and few weapons. The leaders of the tribes did not make money as they believed it was a sin against Aya and all money made from trade went to charity and the people. The Atenian Tribe and Aten An ancient and forgotten tribe, their first known recording in history was 3016 B.D. They made the settlement of Aten, but mysteriously disappeared in 2792 B.D. The native Sorkans blame Tijat. They were an intellectual tribe, many years ahead of their time. Some say this angered Aya and she banished them all. There are many different theories. The Ytrian Tribe and Ytria First appeared in 3002 B.D. Discovered that meat can be used as a food as well, but only certain animals. Also found that they must be cooked as well. Made the settlement of Ytria. They were a barbaric tribe, and were willing to kill at any time necessary. They never took no as an answer. They were the first to also discover armor and mining. The Paramian Tribe and Param One of the first tribes from 3032 B.D. Discovered fire by using wood and sparks from striking two rocks. Made the settlement of Param. This tribe was a feudal type government in which everyone answered to their king of their area. Was the only tribe to have slaves.

My plan is to have the Repnian Tribe win and form an empire on the planet, but I'm not sure how. Can I have any tips how?