The humans originate from the planet of Terra(Also known as Earth) in the Sol System, the Milky Way. They were the only intelligent and the most dominant species of their planet. In 1969 HSC, the first humans landed on the moon, discovering an Ancient Travel Drive, that allowed them to use the Travel Network in order to travel faster-than-light. They quickly expanded throughout the galaxy.
The Human anatomy and psychology is similar to that of many other races that were influenced by them. Strangely, similarities between the Human and the Invader anatomy have been noticed multiple times, suggesting a possible interaction between the Invaders and the ancestors of the modern Humans.