20 September 1066: Tostig Godwinson and Harald Hardrada defeat the English at Fulford. Harold II hears of this and travels north quickly to engage Tostig and Harald.
24 September 1066: Scouts warn the invading army of Harold's rapid advance. Tostig and Harald lay a trap at Stamford Bridge.
25 September 1066: Battle of Stamford Bridge. The Norwegian army engages the English on the eastern end of the bridge. The English easily fall for the bait. Then, disaster strikes. Harald sends a large number of his best troops across an old Roman bridge a mile to the south, shattering the weak English contingent assigned to protect the bridge, and march north, straight into the rear of the English army. By the time Harold realizes what he has fallen into, he is surrounded and under heavy attack from both sides. The Norwegians quickly fight their way into the center and to Harold. The English army is completely destroyed, with 14,400 out of Harold's original 15,000 killed, Harold among them. The Norwegian army marches south.
26 September 1066: William II of Normandy lands in southern England.
29 September 1066: Harald and Tostig reach London and declare Tostig Godwinson to be King Tostig I of England. Knowing that Tostig will be merely a puppet of Harald, the Witenagamot protests, but is quickly silenced.
12 October 1066: Battle of Hastings. William of Normandy attacks Tostig's army, but both an infantry and cavalry charge are unsuccessful at breaching the English shield wall. The Breton division on Williams's left is completely shattered by the elite Norwegian contingents in Tostig's army, and the English surge into the side and rear of William's army. William is killed instantly by a lucky stone-throw by an English infantryman, which breaks his neck. The Norman army collapses, fleeing toward their ships, and are harried all the way by the English, losing 17,500 of their original 22,000, while Tostig loses a mere 6,300 of his original 20,000.
17 October 1066: The shattered remains of the Norman army sail away from England. Upon arriving back in Cherbourg the following day, they are met by Williams's 12-year-old son Robert. Upon finding out about his father's death in battle, Robert becomes Duke Robert II of Normandy.
9 November 1066: Tostig invades Normandy. The Norman army, still reeling after Hastings, is easily defeated at the Battle of Caen. Robert II is deposed and imprisoned in England, and Tostig declares himself Duke of Normandy.
June 1068: A rebellion in Cherbourg is crushed by Tostig.
March 1072: Tostig I dies. Harald Hardrada declares himself King Harald I of England and Duke Harald I of Normandy. He now rules a vast empire, consisting of Norway, England, and Normandy. He starts shooting covetous glances at the other kingdoms in the British Isles and Scandinavia...
Any ideas?