Ireland, meanwhile, remained divided, in a welter of splits and alliances. Nevertheless, from about the 870s, when Olaf returned to Norway and Ivar died, perhaps at Repton, a general pattern emerged. There was not much to be gained by the Vikings any more through raiding for accumulations of money and church treasuries: they had either gone or become much better defended. There was no prospect of land settlement except in limited areas under the control of the Viking ports, like Waterford, Wexford, Limerick and especially Dublin. Where there was still money to be made, it came from slaves, for whom there was steady demand from silver-rich Islam. So what grew up for several generations was ‘A delicate balance . . . between the Norse leaders and the Irish kings of the interior, whereby Dublin survived, for the most part, unmolested, and the Norse for their part desisted from serious attempts at conquest’.