Annex refers to the act of incorporating or joining a territory into an existing country. In the context of history, annexation involves the takeover and control of a region by another nation.
Related terms
Colonization: The process by which one country establishes control over another land or territory for economic or political purposes.
Imperialism: The policy of extending a nation's power through military force or establishing economic and political dominance over other territories.
Manifest Destiny: A belief held by many Americans in the 19th century that it was their divine mission to expand westward and spread democracy across the continent.