A dominant culture is the prominent cultural group in an area that is not influenced by other cultures that may come to the country or region. In the United States, for example, cultures that immigrate to the country pick up the dominant American culture.
While the dominant culture may not transform for future groups of immigrants coming to the region or country, at one time the culture has been influenced by immigrants. In America, for instance, it was influenced by the Puritan immigrants that came to New England and eventually to the Midwest. These immigrants brought values such as a strong focus on literature and learning.