After the departure of the Romans, the wall appears to have fallen to decay, and the City was easily taken by the Saxon pirates, who also neglected defences of this description to a great extent, trusting more to their own valour than in bricks and mortar. It would no doubt suffer greatly in the destruction of its towers and bastions in the three great conflagrations which occurred in the years 764, 798, and 801, and consumed the greater part of the City. Such being the case, it fell an easy prey to the Danes, who in 851 sailed up the Thames with a fleet of 350 ships, speedily reduced it, and garrisoned it as a basis whence to attack Wessex. Alfred the Great succeeded to the throne of Wessex in 871, and from that period to 878 he fought no less than fifty-six battles with the invaders. In 884 he laid siege to London, drove out the Danes and compelled them to capitulate, after which he repaired the walls and forts, and appointed his son-in-law, Ethelred, governor. The repairs appear to have been of a substantial character, as when Anlaf and Swegen, or Sweyn, the kings of Norway and Denmark, attacked the City, with a fleet of 94 ships, in 994, the citizens were enabled to defy all their endeavours to enter within the walls, and compelled them to raise the siege with great loss, as happened again in 1013, when the city was defended by Ethelred II. But after some successes elsewhere, Sweyn returned, and again laid siege to the City; and again the citizens might have closed their gates against him, but Ethelred, their king, pusillanimously fled to Normandy, and the citizens deemed it best to submit, whereupon the gates were thrown open, the Danes admitted, and Sweyn proclaimed King of England. Sweyn did not long enjoy this dignity; he died the following spring, when the Londoners recalled Ethelred: and he also dying soon after. Edmund Ironsides, his son, was proclaimed king, and crowned in London. Canute, the son of Sweyn, however, claimed the crown won by the prowess of his father, and came with a large fleet up the Thames, but could not pass beyond the bridge, and finding he could make no impression on the eastern walls and forts, he cut a canal across Southwark and Lambeth, availing himself of certain watercourses, and conveyed his ships into the Thames somewhere about Vauxhall, whence he sailed downward, and attacked the western walls and towers; but the undaunted bravery of the citizens and the strength of their defences compelled him to raise the siege. Soon after, however, a treaty was entered into between Edmund and Canute for the division of the kingdom: and London falling to the share of the latter, he took up his winter quarters there. By the death of Edmund a few months after, Canute became sole monarch of England.