The ablest king in England in the generation that followed Offa was Ecgbert of Wessex, who had long been an exile abroad, and served for thirteen years as one of the captains of Charles the Great. He beat Beornwulf of Mercia at Ellandune (A.D. 823), permanently annexed Kent, to whose crown he had a claim by descent, in 829 received the homage of all the other English kings, and was for the remainder of his life reckoned as "Bretwalda." But it is wrong to call him, as some have done, "the first monarch of all England." His power was no greater than that of Oswio or Offa had been, and the supremacy might perhaps have tarried with Wessex no longer than it had tarried with Northumbria or Mercia if it had not chanced that the Danish raids were now beginning. For these invasions, paradoxical as it may seem, were the greatest efficient cause in the welding together of England. They seemed about to rend the land in twain, but they really cured the English of their desperate particularism, and drove all the tribes to take as their common rulers the one great line of native kings which survived the Danish storm, and maintained itself for four generations of desperate fighting against the invaders. On the continent the main effect of the viking invasions was to dash the empire of Charles the Great into fragments, and to aid in producing the numberless petty states of feudal Europe. In this island they did much to help the transformation of the mere Bretwaldaship of Ecgbert into the monarchy of all England. Danish invasions. Already ere Ecgbert ascended the throne of Kent the new enemy had made his first tentative appearance on the British shore. It was in the reign of Beorhtric, Ecgbert's predecessor, that the pirates of the famous "three ships from Heretheland" had appeared on the coast of Dorset, and slain the sheriff "who would fain have known what manner of men they might be." A few years later another band appeared, rising unexpectedly from the sea to sack the famous Northumbrian monastery of Lindisfarne (793). After that their visits came fast and furious on the shore-line of every English kingdom, and by the end of Ecgbert's reign it was they, and not his former Welsh and Mercian enemies, who were the old monarch's main source of trouble. But he brought his Bretwaldaship to a good end by inflicting a crushing defeat on them at Hingston Down, hard by the Tamar, probably in 836, and died ere the year was out, leaving the ever-growing problem to his son Æthelwulf. Influence of viking sea-power.