Your best bet might be a separation of England. The southern part was already, prior to 1066, absorbing French/Norman influence, and reducing this might be an uphill struggle. The north of the country, but contrast, was less French and more Scandinavian influence (the old Danelaw business).
Stuck in the middle of them, you've got what is basically (gross oversimplification following) the Anglian regions.
If you somehow (and it is left as an exercise for someone else exactly how) end up with a Norman dominated south, a Scandinavian dominated north, and Mercia and Anglia as a sort of buffer between them, you might keep strong Germanic influences in the middle bit. Maybe Harald wins at Stamford Bridge, and neither William nor Harald can gain an advantage over each other, and end up dividing the country between them. Shortly after, the midlands rebel, and neither Harald nor William are happy for the other to send a large force into the area to tread on the rebellion. Rebellion sort of successful, and survives by constantly playing Northumbria against Wessex and living in no-mans-land.