FitzOsberns seizure of Hereford gave the Normans the principal base for their advance into Wales and established the Marcher earldom that would drive Norman colonisation westward for the next generation.
The size of the opposing forces is not recorded in the surviving sources.
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Aubrey generates in-depth historical research for any location in the UK — drawing on Domesday records, scheduled monuments, Victorian OS maps, geological data and archaeological archives to tell the full story of a place.