Americanist (noun)

1. An expert or scholar in American studies.
2. A specialist in the study of the indigenous cultures of America.
3. An advocate of American political, social, or cultural values and practices.

Origin:

Late 19th century: from american + -ist.

Examples:

1. The Americanist was invited to speak about the cultural significance of the American West.
2. Her expertise in American literature made her a sought-after Americanist.
3. The Americanist movement believed in the superiority of American culture and values.
4. As an Americanist, he focused on the history and cultural heritage of the Americas.
5. The Americanist society aimed to promote a greater understanding of American culture and history.