Final answer:
Historians refer to independent events that occur or change and don't affect each other as 'independent events' or 'unrelated events' in the study of history.
Step-by-step explanation:
Historians refer to independent events that occur or change and don't affect each other as 'independent events' or 'unrelated events' in the study of history. These events are not connected in terms of cause and effect and do not have any influence on each other's outcomes. For example, if we consider the events of World War II, the Battle of Midway in the Pacific and the D-Day invasion in Europe were independent events that occurred simultaneously but did not impact each other directly.