This study takes a postcolonial approach towards second language education in general, and English language teaching as a second/foreign language in particular. It discusses the essences of linguistic imperialism, and goes through the historical, political, ideological, sociocultural, and educational bases of such a discourse. However, it is narrowed down in terms of applied linguistics in TESOL studies. It traces the evidence for such a discourse throughout the world, and then turns to the case of Iran for claiming that Iran, as a postcolonial state has not been unaffected as well.