We were nearly destroyed. That was well over a century ago. Now, with the 23rd century nearing its end, a tenuous state of Cold War exists between the Three Factions of humankind. Each of the factions has claimed a portion of the Human Sphere as its own, linked now by the same Star Gates that broke them apart. But the Universe is large.
Danger stalks the darkness between the stars.
There exist countless worlds, countless discoveries, all drifting through the cold vacuum that spreads outward from Earth and beyond. From there he can pick a profession. So if the player wants to be the ultimate fighter, he will pick the Progen warrior. However, if he primarily wants to be a warrior, but also wants to have some savvy trading skills or explore the far reaches of space, he may choose to specialize in trade or exploration. The same applies to the other races.