Changes

Etymologically, "ξένος (xénos)" is a Greek word meaning "stranger" or "alien".

The major alien races are the [[Ork]]s, [[Eldar]], [[Dark Eldar]], [[Tyranid]]s, [[Necron]]s and the [[Tau]]. All these races pose a considerable threat to the survival and continued dominance of mankind. There are countless other races but all are trivial by comparison.

Many new alien races and civilisations are discovered by Imperial [[Explorator]]s every year. For the most part, these aliens are ignored, contained, or if they present a threat to mankind or the Imperium, eradicated. Throughout its history the Imperium has fought many long wars with dangerous alien species. In most cases the Imperium has eventually won, but in some, the threat has only managed to be contained.{{Fn|2}}

Although friendly dealings with aliens is almost unthinkable, [[Rogue Trader]]s are allowed to barter and trade with aliens.

Despite all the fear and hatred, on certain occasions, short-termed military alliances have been established with the '''Eldar'''. These temporary alliances are somewhat uncommon but not unheard of. They are made against a common enemy like the forces of [[Chaos]], [[Tyranids]] or [[Orks]]. The [[Imperial Navy]], units of the [[Imperial Guard]], and even detachments of Space Marines have, on certain occasions, fought beside Eldar forces. A fine example for this is the [[Gothic War]], during which the Imperium allied itself with the Eldar of the An-Iolus Craftworld against the forces of [[Ezekyle Abaddon|Abaddon the Despoiler]]. No temporary alliances with the [[Tau]] have been made, but short-termed truces have happened.

Some human organisations, including some factions of the [[Inquisition]], individual [[Navigator]] families, the [[Illuminati]] brotherhood, etc., even have certain secret dealings and alliances with the Eldar. All these agreements are carefully guarded secrets, as they would be considered treason by other more conservative factions of the Imperium. One such pact is the [[Coven of Isha]].

Certain individuals, like Captain [[Gabriel Angelos]] of the [[Blood Ravens]] have had friendlier contact with certain Eldar. The Blood Ravens Chapter in particular has had unclear contacts with the Eldar throughout its history. This is, for obvious reasons, kept secret by all parties involved. Ironically, the secrecy surrounding the Blood Ravens' actions with the Eldar could possibly be one contributing factor to the Chapter being largely unaware of its history.