It became a principal market because of its geographical location on a major trade route from northern to southern Germany and Europe. Between 800 and 1000 the growing economic power of the Vikings who held it at this time led to a dramatic increase in the rate of its expansion as a major trading center.
The town was sacked in 1050? by [King Harald Hardraade of Norway]? during the course of a conflict with [King Eric Estridsson of Denmark]?: a Norwegian skald, himself quoted by Snorri Sturlusson, describes the sack as follows: Burnt in anger from end to end was Hedeby [..] High rose the flames from the houses when, before dawn, I stood upon the stronghold's arm
See also: Birka