Not an expert, but I remember a documentary where they were explaining that time period in question corresponded to big changes in English accent and language.

Not an expert, but I remember a documentary where they were explaining that time period in question corresponded to big changes in English accent and language. For example, they were arguing that most English before and going into that time period was pronounced with something similar to a Boston or Irish accent; modern British accents are newer and come from the middle to end of that period. What was happening then to give rise to all this is really interesting to me but I have no idea what it would be. I don't know enough about the history of that region at that time to say.