Ethelfrith, who had effected the conquest of the central and western portion of Northumbria, and may be regarded as the founder of the Northumbrian kingdom, "conquered," as we read in Beda, "more territories from the Britons than any other king or tribune;" but although he was thus able to overrun a vast district of country, his followers were not sufficiently numerous to colonise it. In some places, indeed, "he expelled the inhabitants, and placed Angles in their stead," but "in others," and doubtless to a much greater extent, "he allowed the vanquished to retain their lands, on payment of tribute." In the reign of Edwine, too, the Anglo-Saxon population were under his immediate government; the petty British States were still ruled by tributary princes. And no doubt their political condition continued more or less the same during the century and half which preceded the dissolution of the Heptarchy, and after the reconstruction of its several parts under one crown. On Northumbria being overrun by the renowned Danish Viking Healfdene, A. D. 875, fifty years after the Heptarchal kingdoms had been dissolved, it is recorded that the indigenous inhabitants of the part called Cymriland, the Cumbrians, or Britons, being too weak to defend themselves from the hateful aggressions of the Danes, and deprived of the protection of the Saxon kings of Northumbria, who had themselves succumbed to the common enemy, turned for aid to the only neighbours who seemed sufficiently powerful to resist the invaders. They therefore implored the aid of Grig or Gregory, king of Scotland, by whose assistance in the following year the Scandinavian ravagers were expelled. These Indigenoe, or British inhabitants, must have been the people of Galloway, and of the district around Carlisle; for the Strathclyde Britons were already under the authority of Gregory, as the guardian of Eocha, a minor, who, as the son of Hu king of Strathclyde, and nephew of the second Constantine, king of Scotland, succeeded to the crowns of both these realms. Whether the Britons subsequently quarrelled with their powerful ally, and being defeated in battle, were obliged to cede to the victor their rocky highlands and adjacent places; or they voluntarily submitted themselves to Gregory, with their lands and possessions, thinking it preferable to be subject to the Scots, who, although enemies, were Christians, than to infidel pagans, there does not appear to be any evidence to determine.