What if Harold died at Stamford Bridge, not Hastings?

In 1066, three men vied for the English throne. Harold Godwinson seized it first, but he would have to fight to keep power. He defeated one rival, Harald Hardrada, at the battle of Stamford Bridge, before meeting his fate at Hastings against the duke of Normandy, best known as William the Conqueror.

It was a turning point in English history, which saw the end of Anglo-Saxon rule and ushered in the Norman Conquest, and one that has been dramatised in the BBC's King and Conqueror.

Surely, to change a major detail of that tumultuous year – such as Harold dying at Stamford Bridge in September 1066 rather than Hastings, fought in October – would have monumental repercussions on the political, cultural, religious and social changes that followed.

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Perhaps not, though, according to Dr Marc Morris, a historian, broadcaster and author specialising in the Middle Ages. “I don’t think it would have made that much difference in the long term,” he says. “Almost all of the changes that took place in England as a result of the Norman Conquest would still have taken place anyway, whether or not there was a Norman Conquest.”

William’s victory against Harold at Hastings ended Anglo-Saxon rule and established a new elite class, with profound impact, but many of the Norman upheavals actually represented the shifting attitudes in Europe at the time, says Morris.

“Castles, Romanesque architecture, the demise of slavery, the introduction of chivalry: all of these things were becoming the norm across the continent, across the Frankish-speaking world.”

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They would have come to England eventually, although over several generations rather than virtually overnight, as seen under the Normans. “The only exception is that we wouldn’t have such a crazy language as modern English, because it wouldn’t have had the French overlay,” adds Morris.

Besides, was it possible that Harold’s death at Stamford Bridge – against the invading forces of the king of Norway, and rival claimant to the throne, Harald Hardrada – would have prevented the Norman Conquest in the first place? Such battles always came with an “element of random death”, as Morris puts it, given the volume of arrows flying around. “Harold could have been killed at any point, no pun intended.”

Harold could have been killed at any point, no pun intended

His death would almost certainly have ended Anglo-Saxon hopes at Stamford Bridge, and would have been seen as a judgement on the legitimacy of his claim to the throne. In need of another claimant to stand against the invading Norwegian warriors, and the threat of William’s Normans down south, Anglo-Saxon leaders – much like they did in reality after Hastings – would have turned to Edgar Aetheling, the teenage great-nephew of Edward the Confessor.

Meanwhile, Harald Hardrada and his ally Tostig, brother of Harold and, says Morris, “a fifth columnist”, would have been celebrating two major victories in the space of a week. Five days before Stamford Bridge, they defeated the earls of Mercia and Northumbria at the battle of Fulford, before taking control of York. Now, they could march south and take London, putting an end to Edgar’s reign before it even began. “I wouldn’t imagine much in the way of opposition, so Harald would have had a coronation,” suggests Morris.

Of immediate concern, however, would have been the duke of Normandy’s landing, which took place on the Sussex coast on 28 September, just three days after Stamford Bridge. Whereas Harold relied on the strategy of surprise and raced down to meet William straight away, a victorious Harald Hardrada and Tostig were unlikely to move with the same speed and urgency. “If they took time to recover their strength and have a celebratory feast, they would have still been in the north when William landed,” says Morris.

Harald Hardrada and Tostig may have chosen not to come south until their hold on the north had been consolidated, if they refused to rise to William’s harrying of Sussex; a baiting tactic used to great effect against Harold. They then could have waited for reinforcements from Norway and began preparations for a battle (if not a war) against the Normans.

William, on the other hand, could not have waited forever, Morris asserts. “He would eventually have moved inland, not least so his troops would have food to live off. The difficulty there is that once they started foraging, they left themselves exposed to attack.” Like the other invaders in the north, though, William would have set about preparing for a campaign for the crown.

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This does raise the question of whether the two sides could have reached an agreement whereby they split control of England, similar to Cnut and Edmund Ironside’s truce following the battle of Assandun in 1016. But that had only lasted a few weeks, as Edmund died on 30 November 1016.

And if that was the case, Morris questions how long such peace could last. “You can’t share the crown. I can’t see Harald Hardrada or William settling for a half measure. It would come to blows. There would be weeks, running into months of warfare,” he explains. “Who wins? We don’t know. In terms of reputation, you can’t get as much as a cigarette paper between the two, so it would come down to luck; who had God’s favour on the day.”

Ultimate victory for Harald Hardrada, followed by a reign long enough to secure his rule and succession, would have resulted in a situation similar to Cnut’s, half a century earlier, according to Morris. “He was still king of Norway and had Scandinavian lands to rule, and would have to return to them. He was not going to stick around in England,” he states, and puts forward Tostig as the likely placeman to rule in his stead.

I’d put my money on William, because he was smarter

“Having said that, Harald Hardrada failed to see Harold coming and his warriors went off to Stamford Bridge without their armour, so that doesn’t exactly suggest that he was a details man,” Morris concludes. “I’d put my money on William, because he was smarter.”

In the case of William winning the throne, even if it might have taken longer than it did in reality, the Norman Conquest would have got underway in the much the same way it did after Hastings. Instead of 1066, however, the history books would talk of a different year as being a turning point in the story of England.