The open door policy was designed to open Japan to American trade and influence (The US was hungry for an imperial puppet).
The fortified hill being described here is named Acropolis.
Acropolis is one of the most recognizable and important sites in the Greek history and culture. Acropolis means the "highest city" in literal translation and the word itself is used for many other similar sites but only the Acropolis of Athens is known as The Acropolis. The most famous building here is without a doubt Parthenon.
A.
Slaves sent to the Caribbean and South America did not live long because of the harsh climate, diseases, and terrible living conditions.