In wartime, five hides were expected to provide one fully armed soldier in the king's service, and one man from every hide was to provide garrison duty for the burhs and to help in their initial construction and upkeep. The continued maintenance of the burhs, as well as ongoing garrison duty, was also probably supplied by those inhabitants of the new burhs which were planned by the king as new towns. In this way the economic and military functions of the larger burhs were closely interlinked. The hide also served as a unit of fiscal assessment for the collection of a tax, known as Danegeld, for which the original purpose was to raise money to buy off raiding Vikings; however after that threat had retreated it was retained as a permanent land-tax.