The Witenagmot was a council of Anglo-Saxon high ranking people brought together to assist in the running of the country alongside the Anglo-Saxon kings of England. The council members included bishops, ealdorman and thanes, high ranking Anglo-Saxons. The council is also known as the Witan.
Edmund II became king at the death of his father Aethelred II in London. London chose prince Edmund as king but it was short lived as the Southampton Witan chose Canute, who then invaded England.
Aelfgar, earl Mercia was outlawed by the witan. He built a force and allied himself with Welsh Gruffydd ap Llywelyn. They raided Hereford and eventually came to terms with Harold. Aelfgar was later restored. 2
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Selection of references used:
1. Timbs & Gunn, Abbeys, Castles & Ancient Halls of England & Wales