The two ways of acquiring U.S. citizenship at birth are by place of birth and inheritance from U.S. citizen parents. Any child born in the United States while under American jurisdiction is a U.S. citizen at birth. Because foreign ambassadors are not subject to American jurisdiction, children born in the United States to foreign ambassadors do not obtain U.S. citizenship at birth. Children born overseas to U.S. citizen parents derive U.S. citizenship at birth, as long as the parents previously lived in the United States for a sufficient period of time. All others must naturalize to become citizens. J.B. was not a U.S. citizen at birth.