During this year, it is thought, William used the exiling of Godwin to Flanders to visit Edward the Confessor in England. Edward spent most of his youth in France, so probably welcomed this visit. Why William chose to visit Edward at all is open to question. Whatever happened on this trip, words were exchanged that gave William the impression that when Edward died , he would automatically become the new king of England. If that was his plan, he could not have picked a better time with the Godwins in disgrace. The news of the coronation of Harold a few months earlier must have infuriated William. After Harold's oath of 1064 and the promise made to him by Edward the Confessor, he must have considered all his options until he was left with only one. To this end, he prepared himself for invasion. Duke William would have discussed his plan with his half brothers Odo and Robert to see if it was viable. With their support he called a council of war. This would be made up of his immediate family, vassals and advisers. The council of war took place at Lillebonne. When Williams plan was put before the council, it was met with derision. Even though understood their commitment, their was no provision for fighting overseas. As hard as William tried to persuade them, the council eventually broke up in disarray. This made William very angry. William being William however, did not give up. He was determined and resolute enough to get his way. If he could not persuade them at the council, he would try on a one to one basis. Eventually he gained support from his vassals. William realised that he would have to turn this trip into a crusade. To do this he would need the blessing of the Pope. He managed this by persuading the Pope of Harold's promise and treachery. At first the Pope refused on political grounds because of the implications to the Church. Pope Alexander II was a pupil of Lanfranc who was now a trusted adviser to William. It was this fact that his blessing was eventually given. William now had the papal banner on his side. This made it much easier to rally his men to arms. Harold now king of England, was about to meet a challenge from invaders from across the North Sea and the English Channel in the coming months. Tostig, as mentioned earlier, was declared an exile and had departed, only to return some time later, undertaking attacks on the English coastline. He invaded the Isle of Wight in May 1066 and continued ravaging other locations along the south. With his mercenary force he was limited in his success, partly due to the Earls Morcar and Edwin.

He found an ally in Malcolm, king of the Scots. With his assistance, Tostig raided the Northern kingdoms. To Harold II, the exploits of his renegade brother must have caused him some concern. Although Tostig became a thorn in the side of Harold, he would not have seen him as a threat to the kingdom. Harold was probably more concerned with the activity that was taking place in Scandinavia.
Harald Hardrada, the king of Norway was a giant of a man in stature as well as deed. His very name meant hard council. His exploits were legendary. He was ruthless and mercenary, his blood lust knew no bounds. Hardrada had been a seafarer from an early age. All through the early months of 1066, Hardrada prepared his invasion force. Hardrada knew that England had a large population of Scandinavian settlers from past campaigns, who he hoped would give him their allegiance. This was no ordinary campaign for Hardrada, he obviously knew of the fate of previous expeditions to England but his arrogance, blood lust and piratical mentality overcame any caution he may have had. It was in 1066 that there was a visitation by Haley's comet which had not gone unnoticed by them. A comet was considered to be an omen of bad luck. Even so, Hardrada set sail.
Across the English Channel, another claimant to the English thrown was making preparations to collect his prize. William Duke of Normandy, in his eyes the only true claimant of the thrown of England after the promise made to him by Edward the Confessor and the pledge of allegiance made by Harold under duress. Hardrada and William were not the only ones who could make a claim to the English throne.
Sweyn Estridson, king of Denmark could also have made a claim to the throne. Being a nephew of Hardicanute and grandson of Sweyn Forkbeard, would have been a serious candidate. His major concern was with Harold Hardrada and his aborted plans to invade Denmark. To this end, he threw his support behind William. His spies would have informed Harold of the build-up from beyond the North Sea and across the English Channel in Normandy. To this end, he made his plans to counteract any invasion force that might threaten his kingship. It was important to him to unify the country to combat the imminent danger. He travelled north to pacify Edwin and Morcar, who had bad memories of Harold's brother Tostig and his draconian measures in Northumbria. To cement the alliance he married Edith, the sister of Edwin and Morcar.