On the 5th January 1066, Edward the Confessor died. He had no heir to the throne so it was unclear who would become the new king. As there was no clear line of succession, there was four men who stated that they had a claim to the throne. These were Edgar Aetheling, Harold Hardrada, Harold Godwinson and William Duke if Normandy. On the same day as Edward's funeral, Harold Godwinson was crowned king.
He knew that Hardrada and William would try to claim the throne so Harold stationed his army under leadership in the south to wait for William's invasion. He left some in the north under the command of earls Edwin and Morcar. They waited all Spring and Summer but when September came Harold had the let the Fyrd (ordinary peasant soldiers) to go home to their harvests.
20th September 1066: Vikings invade, Battle of Fulford Gate. Just outside York, Hardrada, Tostig and around 7000 soldiers invade England. Only a few Norwegians arrive at first and the English won an advantage through superior numbers and the element of surprise. However, more vikings arrived which eventually overwhelmed the Angelo-Saxons. Hardrada wins but both sides suffered losses. The Northern army was disorganised; Edwin and Morcar were forced to flee.
Godwinson travels from London to Stanford Bridge in 5 days. AS he travels 300km North, he collects as many soldiers as possible to gain the biggest army when there. The defeat at Fulford meant that Harold had to move quickly to deal with the viking invasion. This lead to the Battle of Stamford Bridge on the 25th September 1066. Hardrada had had some heavy casualties at Fulford.
The army was spilt across the River Derwent meaning many didn't have armour. Harold launched a surprise attack on the Viking camp. Vikings were scattered and not ready as they had not defended the bridge properly. The viking berserker defended the bridge and killed 40 men with his bare hands while the others tried to prepare. The battle was long and bloody leading to Hardrada and Tostig both being killed. Only 24 of the 300 ships were needed after.
Three days after the battle, 28th September, William landed on the south coast of England. This meant that Harold had to race to the south placing him at a disadvantage. Him and his soldiers had no time to rest and recover while William and his men were preparing well and setting up castles. They were well organised and most likely to win at the point in time.