William has meanwhile assembled a large invasion fleet and an army gathered from Normandy and the rest of France, including large contingents from Brittany and Flanders.

He has spent almost nine months on his preparations, as he has had to construct a fleet from nothing.

According to some Norman chronicles, he had also secured diplomatic support, although the accuracy of the reports has been a matter of historical debate.

The most famous claim is that Pope Alexander II gave a papal banner as a token of support, which only appears in William of Poitiers's account, and not in more contemporary narratives.

William had mustered his forces at Saint-Valery-sur-Somme, and was ready to cross the English Channel by about August 12, but the crossing had been delayed, either because of unfavorable weather or to avoid being intercepted by the powerful English fleet.

The Normans cross to England a few days after Harold's victory over the Norwegians, following the dispersal of Harold's naval force.

William lands in Sussex on September 28 on the south coast between Pevensey and Hastings.

A few ships are blown off course and land at Romney, where the Normans fight the local fyrd.

The ships used by William to invade England are (judging from the Bayeux Tapestry celebrating the event) similar to Viking longships, except for being partially decked and having a corvus (small castle) at bow and stern, from which soldiers can use their bows and arrows against the enemy before they draw near enough enough to board.