What decisions were made at yalta and what role did they play in the emergence of the cold war

Probaly when they divided the area of Berlin into sections. That then got split in half between West Germany (anti-communist) and East Germany (pro-communist), which led to tensions between the US (West Germany) and the Soviet Union (East Germany).

disease was the number one killer of native peoples. they had had little exposure to the diseases of europe. this led to some villages being almost completely wiped out and some tribes destroyed.