Após algumas pesquisas, parece que o Império era racista / xenófobo. Essa política até tem um nome: " Alta cultura humana "
Human High Culture was the Galactic Empire's codified policy of Humanocentric speciesism. It centered around the belief (long, if privately, held by a minority of Humans in the Human-dominated Core) that Humans were inherently superior to other species.
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As such, through the repealing of such laws as the Rights of Sentience and the creation of new acts, all nonhumans were made second-class citizens (if citizens at all). Non-Human slavery was re-legalized. Only 'pure' (i.e., those made exclusively by Humans and with no help from nonhumans) works of art (such as operas, holovids, books, etc) were allowed to be produced, viewed, and spread, since only Human culture was worthy enough to be allowed to prosper in the New Order. Non-Humans were 'actively discouraged' to participate in government or join the Imperial military, and Human governors and moffs were placed in command of nonhuman worlds and sectors.
Quanto ao próprio imperador, não é assim tão claro:
[...] It is debatable to what degree, if at all, Palpatine was a speciesist. Palpatine freely consorted with nonhumans such as Mas Amedda and Sly Moore, as well as taking Darth Maul as an apprentice, of which all were Humanoid, therefore it might be suggested that as a Sith, Palpatine's Humanocentrism was more liberal than that of the standard Imperial sort, possibly due to the fact that Sith throughout history were predominantly either Human or Humanoid. From this viewpoint, it is conceivable that Palpatine's (Sidious) Speciesism was more broadened in that to include certain Humanoid species and he used anti-alien sentiments as a way to divide the beings of the galaxy and help consolidate his rule. After all, one of the worst atrocities Palpatine committed was the destruction [of] the Human-dominated world of Alderaan. He also ordered the creation of an exclusively Human-killing pathogen.