Origins and development
The term ethnocentrism is believed by scholars to have been created by Austrian sociologist Ludwig Gumplowicz in the 19th century, although alternate theories suggest that he only popularized the concept as opposed to inventing it. He saw ethnocentrism as a phenomenon similar to the delusions of geocentrism and anthropocentrism, defining Ethnocentrism as "the reasons by virtue of which each group of people believed it had always occupied the highest point, not only among contemporaneous peoples and nations, but also in relation to all peoples of the historical past."
Subsequently in the 20th century, American social scientist William G. Sumner proposed two different definitions in his 1906 book Folkways. Sumner stated that "Ethnocentrism is the technical name for this view of things in which one's own group is the center of everything, and all others are scaled and rated with reference to it." In the War and Other Essays (1911), he wrote that "the sentiment of cohesion, internal comradeship, and devotion to the in-group, which carries with it a sense of superiority to any out-group and readiness to defend the interests of the in-group against the out-group, is technically known as ethnocentrism." According to Boris Bizumic it is a popular misunderstanding that Sumner originated the term ethnocentrism, stating that in actuality he brought ethnocentrism into the mainstreams of anthropology, social science, and psychology through his English publications.
Several theories have been reinforced through the social and psychological understandings of ethnocentrism including T.W Adorno's
The Authoritarian Personality Theory (1950), Donald T. Campbell's Realistic Group Conflict Theory (1972), and Henri Tajfel's Social Identity Theory (1986). These theories have helped to distinguish ethnocentrism as a means to better understand the behaviors caused by In-group and Out-group differentiation throughout history and society.