There are many such examples. The ones that spring to mind most immediately would be the Crimean Tatars, who were deported from Crimea by the Soviet government, but who still identified - and identify - themselves very strongly as being Crimean Tatars. Indeed, the same can be said to varying degrees of a lot of the people the Soviets deported.
Native Americans, too, are another good example of a long-term displaced peoples who still identify as their particular ethnic group. The Cherokee, for instance, aren't from Oklahoma, but there is a large population of them there who most definitely identify themselves as Cherokee. This sort of continued identity can be found in many, many groups of Native Americans.
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