Sorry it's taken so long to get back on this. Been busy chasing my tail!
Hereward WAS a bane, that's understood. To begin with, can I put you on the right track about Herward himself?
Hereward was the thegn of Bourne in Lincolnshire, who had been assigned bookland by the abbot of Crowland Abbey in eastern Lincolnshire. Before he took possession he left England for Flanders - modern day Belgium - and carved out a career for himself there before returning to England in 1066, shortland after Duke William's closely-fought victory near Hastings. On finding that his younger brother had been slain by the Normans he set out to destroy the killer. He took part in the sack of Peterborough Abbey, ostensibly to prevent the abbey's treasures from falling into the hands of the newly appointed Norman abbot Turold. The Danes under the command of Svein Estrithsson carried away many of th treasures as well as some of the monks. Later he took a leading roie in the siege of Ely, making forays against the Normans and their defences. When finally King William gained access to Ely by way of a track he was made aware of by a monk, Hereward made his escape inland to an area known to us as the Brunesweald. Finally he gained passage back to Flanders with other Englishmen into exile. The Norman baron, Hugh d'Envernmeu who was given Hereward's lands thought to gain credibility, or 'roots', by adopting the byname 'Wake'.
There is a book, THE ENGLISH RESISTANCE by Peter Rex, published by Tempus (ISBN 0-7524-3733-X) which describes Hereward's history and activities against the Normans from page 112-193. In parts it is hilarious, such as when the Normans brought a local witch to one of their wooden towers to put a curse on Ely's defenders. At the end of her incantation she turned and bared her backside. An arrow found its mark, the tower was set on fire next by another arrow and the crone broke her neck falling to the ground!