According to Wikipedia:

Monoculturalism is the practice of actively preserving a culture to the exclusion of external influences. It should not be confused with a homogenous society, which is one with racial uniformity, but some possible exposure to foreign culture. An example of a homogenous society of this sort would be Japan, where American post-war cultural influence has modified the traditional society to some extent. Iceland, North Korea, and Spain under Francisco Franco are examples of monoculturalism. Usually a monocultural society exists due to undeveloped communications structures, geographic isolation, or political isolation (sometimes but not always under a totalitarian regime). Bhutan could also be said to be monocultural.

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