The machine gun was decisive in securing victories for the Allies in WW1, if that's the time period this is focused on.
It was easier for students to read and learn about different subjects. Since there were so many books printed, it was cheaper for learning students.
Hope this helps a little
To give you a little background, the 5th century was a time period where the roman empire had two kings. One to rule the west and the other to rule the east. This made it easier to oversee the entire land. (Rome was the biggest empire ever recorded.) By the end of the 5th century, though, western Rome had fallen to the hands of their enemies while the eastern part held their ground. Anyways, during the 6th century the overthrow of the roman monarchy took place, they vowed to never let another king rule over Rome again. Eventually a dictatorship resulted.
