In Medieval time (no pun intended) the only people who knew how to read or write were people whom worked in the church. Simple merchants and farmers did not have time to learn because they helped with the family trade as soon as their caregiver decided they were old enough.
Answer:
to add important words to get a better understanding
Explanation:
I think the answer your looking for is “blitzkrieg”
It blockade access to berlin
The technology necessary for navigating such journeys had not yet been invented. Ships had to become better, then they needed maps and charts, compasses, and anything similar.