irisharchaeology:In AD 1029, Amlaíb son of Sitric, the Viking king of Dublin was captured by Mathgam
irisharchaeology:In AD 1029, Amlaíb son of Sitric, the Viking king of Dublin was captured by Mathgamain ua Riacáin, king of Brega who released him only after a huge ransom was paid, part of which included ‘six score Welsh horses’. (Annals of Ulster) -- source link