Ilos, situated in the Ilos system within Hutt Space of the galaxy, was a rather unremarkable planet primarily known for its agricultural activities; it could be found along the Pabol Sleheyron hyperlane, which provided a route between Chalacta and Ilos Minor.
This planet served as the original homeworld for the sentient Ilosian species; many millennia prior to the significant Battle of Yavin, the Ilosians left their home and established colonies on numerous planets in the surrounding area.
The initial mention of Ilos occurred in The Essential Atlas, a reference book from 2009 that was jointly created by Jason Fry and Daniel Wallace; the book identified the planet's location as grid square R-10.