Was the Exodus natural or supernatural, fact or fiction?

[Justtristo]

A system which worked so well that Alfred the Great built forts to stop the Vikings because English field armies had such great success against the Vikings.

Alfred the Great prevented the kingdom of Wessex being conquered by the Norse, (which happened to every other Anglo-Saxon kingdom). Later in his reign Alfred conquered the former kingdom of Merica and laid the foundations for the Kingdom of England (which has lasted until this day). He wasn't called the Great for nothing.

[Minimalist]

Most of the time the Vikings didn't really go around looking for field armies to fight. Against raids forts made sense.

I didn't say that it didn't work. I said it avoided pitched battles by forcing the Vikings to attack fortified positions.