Hi. You did not present the cover of the magazine to which this question refers, which makes it impossible for this question to be answered. However, I will try to help you as best I can.
A historical circumstance refers to a condition for a historical event to happen, that is, this circumstance is referring to a historical event that caused another historical event of greater impact and proportion. Therefore, to answer your question, you must analyze the cover of your magazine and identify which circumstance, which historical event, which provoked another historical event, this cover addresses.
Ruler !!! I think
Sorry if it's wrong
It made you able to mass produce products witch made more jobs for people
The Lusitania. It was torpedoed without any warning off the south coast of Ireland. 1,198 out of the 1,959 passengers/crew drowned.