The Battle of Brunanburh took place in 937, and is often referred to as the battle that made England. But there are a LOT of questions about that battle, including how it played out and where it took place.
Research:

SYMHC Classics: Dr. Lucy Hobbs Taylor
29:58

Behind the Scenes Minis: Carry-on Bags
28:38

Gustave Flaubert and the ‘Madame Bovary’ Trial
45:15