Ethnic group

Ethnicity or ethnic group is a socially defined category based on common culture or nationality.

Among the first to bring the term "ethnic group" into social studies was the German sociologist Max Weber, who defined it as:

[T]hose human groups that entertain a subjective belief in their 
common descent because of similarities of physical type or of customs 
or both, or because of memories of colonization and migration; this 
belief must be important for group formation; furthermore it does not 
matter whether an objective blood relationship exists.