Enormously different; the battle of Hastings changed everything. The death of Harold and hundreds of other powerful men in 1066, as well as during the years of rebellion that followed, quickly led to the disinheritance of an entire ruling class.
The Domesday Book shows that by 1086 less than 10 per cent of England’s top 7,000 landowners were English; henceforth all the earls, bishops and barons were continental newcomers. They brought with them a new language of government (Latin); a new style of architecture (Romanesque); new ideas about warfare and fortification (castles); and new attitudes towards life itself. The Normans, for example, introduced the concept of not killing your enemies once they had surrendered (chivalry) and hastened the decline of slavery.
Some of these changes might have happened gradually without the Conquest. But had William been peacefully accepted as king he would have been much less powerful. He would have been a foreign prince surrounded by powerful English earls, not least Harold Godwineson – in much the same situation as his predecessor Edward the Confessor. Without the battle of Hastings there would have been no aristocratic revolution and without that no changes in language, law, architecture and attitudes. As William of Malmesbury wrote in the early 12th century, 14 October 1066 was “a fatal day for England, a melancholy havoc for our dear country brought about by its passing under the dominion of new lords”.
Answered by: Marc Morris, author of The Norman Conquest (Windmill Books, 2013)