Harold the Second had just defeated Harald Hadrada in the Battle of Stamford Bridge and was marching his troops over 300 miles to battle William of Normandy.
Meanwhile, William of Normandy was quickly building huts and resting soldiers for the battle ahead.
When Harold arrived in Kent, where William was based, he arranged his troops in a shield wall at the top of the hill even though he knew they were very tired from marching all that way.
Williams troops couldn't get through the shield wall so they thought up a very clever plan: they would pretend to retreat so that Harold's troop would break out of formation. Then, they would turn back around and kill all of Harold's troops to win the battle.
William's troops ran away and Harold's troops fell for the plan, breaking out of formation to chase William's troops.
Williams troops then turned around and won the battle against Harold's Troops.