Note 53 — Chapter II · INTERCOURSE BETWEEN THE GAILL AND THE GAEDHIL DURING THE VIKING PERIOD.

The plundering of these burial-mounds—“a thing that had never been done before”—made a deep impression on the Irish Annalists; it was thought that the Vikings discovered the existence of the treasure by magic, “through paganism and idol worship” (War of the Gaedhil with the Gaill, p. 115). The same source (p. 25) records the plundering of Kerry by Baraid (O.N. Barthr) and Olaf the White’s son “who left not a cave there underground that they did not explore.”

Several references to this practice of the Vikings occur also in Icelandic literature. It is interesting to compare the Irish accounts with the following passage from Landnámabók (I., ch. 5): “Leifr (one of the earliest settlers in Iceland) went on a Viking raid to the West. He plundered Ireland and found there a large underground house (Icel. jarth-hus). It was dark within until he made his way to a place where he saw a light shining from a sword which a man held in his hand. Leifr slew the man and took the sword and much treasure besides.”