The Anu'anshee were one of the first warp-capable races in the galaxy. They eventually constructed an outpost in the Eris Alpha system. By the 22nd century, they had vanished, though traces of them remained in the Ondahar, Kandoge and Camus systems.

In the Eris Alpha sector, they were also known as the Krytallans and Irakua. In the Cyrean language, Anu'anshee means "those who preserve," and it is possible that they were the Preservers. (ENT novel: What Price Honor?)

The novel What Price Honor suggests that the Anu'anshee created the technology shown in the TOS episode "Turnabout Intruder".