 The succession of Áed led to another series of alliances between natives and invaders.The Norsemen of Dublin now allied themselves with Lorcán mac Cathail, one of the rival kings of Mide.In 863 Lorcán, Amlaíb, Ímar and Auisle invaded Flann mac Conaing's kingdom of Brega, during which invasion they plundered the megalithic tombs in the Boyne Valley, an unprecedented act of sacrilege.