https://en.m.wikipedia.org/wiki/Ethnic_issues_in_China

According to historian Frank Dikötter,
A common historical response to serious threats directed towards a symbolic universe is "nihilation", or the conceptual liquidation of everything inconsistent with official doctrine. Foreigners were labelled "barbarians" or "devils", to be conceptually eliminated. The official rhetoric reduced the Westerner to a devil, a ghost, an evil and unreal goblin hovering on the border of humanity. Many texts of the first half of the nineteenth century referred to the English as "foreign devils" (yangguizi), "devil slaves" (guinu), "barbarian devils" (fangui), "island barbarians" (daoyi), "blue-eyed barbarian slaves" (biyan yinu), or "red-haired barbarians" (hongmaofan).