The Altarians do not call themselves Altarians. It is the term humans call the residents of the third planet orbiting Ara Centauri. Known as "The Altar", it has become simply known as Altaria since it is the only planet with intelligent life in that part of the galaxy.
The evolutionary history of the Altarians is a story on its own. The Altarians name for their own planet is loosely translated as "Elemental". But how they evolved on this world is something of a mystery.
Long ago, a sentient species evolved from warm blooded lizard-like beings that became known as the Drath. And yet, multiple humanoid species evolved in a short amount of time despite the lack of any primate species on the planet.
There are many theories on how so many different sentient species could arise on the planet. But the various myths and religions on Altaria insist that it was the result of the presence of the dark Mithrilar Draginol whose influence caused a single humanoid species to evolve alongside the Drath. This attracted the Precursors whose conflict had not matured.
The Precursors fought a series of proxy wars using the fledgling Altarians as their clients. Different Precursors modified the young Altarians in different way resulting in a series of subspecies and early nations. The Drath found themselves in the middle of this conflict and eventually was forced to flee the world with the help of sympathetic Precursors.
In the meantime, a series of incredible wars were fought out on Altaria with different factions laying claim to the world. At the end of one particularly brutal war, the planet is nearly destroyed in what becomes known as the cataclysm. Nearly all life on the world is wiped out.
While the world recovers, the war between the Precursor factions raged across the galaxy in what becomes better known as the Arnor/Dread Lord wars. The war is concluded just as the world begins to heal itself.
The post-cataclysm Altaria recovers slowly with different factions vying for control. The world itself is littered with artifacts of the Precursor wars which threaten to ultimately destroy the world again.
Much of the history between the rebirth and modern Altaria is lost. What is known is that the modern Altarians are highly peaceful and benevolent. They also have the genetic ability to manipulate what is known as "dark energy". It is a difficult concept to grasp. Just as different species can recognize different light spectrums, the Altarians have the capability to inherently make some use of dark energy.
This inherent ability has only limited use in a technological society. As the rise of the Drengin Empire and Arcean Empires show, technology is the ultimate equalizer.
Physically, Altarians look identical to humans. They are not, however, humans. They are not genetically compatible and do not share the same DNA. But they are similar enough in DNA to ensure that there is some unknown connection between the two.