Consisting of Norfolk, Suffolk, Cambridgeshire, Hertfordshire, and Essex (Lincolnshire was added later), this was the only one of the parliamentary county associations to enjoy any permanence in the Civil War
. Its purpose was to break down the reluctance of local levies to venture outside their own counties. Based in Norwich, the association was ordered to raise an army of 20,000 men with Manchester
as commander-in-chief and Oliver Cromwell
as lieutenant-general of the cavalry. While its chief function was to protect the rich and populous eastern counties, the army later ventured further afield, most notably at Marston Moor
(July 1644). This stunning victory heralded the break-up of the association, since it fanned the flames of antagonism between Cromwell and Lawrence Crawford, the Scottish major-general of foot. The quarrel seems to have demoralized Manchester, who became increasingly reluctant to fight after Marston Moor
. The public recriminations that erupted between him and Cromwell led to the absorption of the Eastern Association army into the New Model
in the spring of 1645, and the eventual demise of the association itself.