Although Rǫgnvaldr is not mentioned in the Irish annals, other historical sources indicate that he indeed had Irish connections. For example, "Orkneyinga saga" notes that, when he lent military support to William in Caithness, Rǫgnvaldr led a large army drawn from Ireland. Also linking Rǫgnvaldr to Ireland is Henry III's summons to Rǫgnvaldr, dated 16 January 1218, commanding him to explain the "excesses committed upon the people of our Lord the King, as well in England as in Ireland". "Baile suthach síth Emhna" also reveals connections with the island. Although the poem undoubtedly exaggerates Rǫgnvaldr's feats, its claims of devastating raids into Ireland may not be complete fantasy, as evidenced by the summons.