Dathissmir is a rather large jungle planet located in the Carina-Sagittarius arm of the Milky Way Galaxy. Dathissmir is a planet green in coloration, boasting a hot, humid climate and an extremely hostile environment. The planet is around twice the size of Earth.
Dathissmir is home to an unknown number of species and intelligent races, however, it is most prominently the homeworld of the infamous Thissmirians, a race of large snake-like near-humanoids that have developed a space-faring society and have conquered several neighboring worlds and star systems.
According to scientists who have studied Dathissmir, the Thissmirians are the dominant species on the world, and have subjugated several "weaker" intelligent life forms into servitude of their empire. Dathissmir is governed by a monarchy headed by the Queen of the snake-people.
In the year 2154, the Thissmirians dispatched a fleet to Earth, launching an invasion of the planet in an attempt to bring it under rulership of the Dathissmirian Empire. However, the invaders were defeated and they returned to their homeworld. Since then, the planet and its inhabitants have remained quiet.