Diarmuid Ua Duibhne

Diarmuid Ua Duibhne (Irish pronunciation: [ˈdʲiəɾˠmˠədʲ uə ˈd̪ˠʊvʲnʲə]) or Diarmid O'Dyna (also known as Diarmuid of the Love Spot), was the son of Donn and one of the Fianna in the Fenian Cycle of Irish mythology (traditionally set in the 2nd to 4th century). He is best known as the lover of Gráinne, the intended wife of Fianna leader Fionn mac Cumhaill in the legend The Pursuit of Diarmuid and Gráinne.

In the legend, the Tuatha Dé Danaan god of love and creativity Aenghus Óg was Diarmuid's foster father and protector. According to the story Diarmuid was a skilled warrior and a well-liked and valued member of the Fianna who single-handedly killed 3,400 warriors in a battle and saved Fionn and the Fianna.

Aengus Óg owned a deadly sword named Móralltach or Nóralltach – the Great Fury, given to him by the sea-god Manannán mac Lir (Mananaan Son of the Sea). In The Pursuit of Diarmuid and Gráinne it is said of Móralltach that it left no stroke nor blow unfinished at the first trial. Aonghus gave this sword to his foster-son Diarmuid, in addition to a sword named Beagalltach, the Little Fury. Along with these two swords, Diarmuid is known to have wielded two spears, Gáe Buidhe (Yellow Spear) and Gáe Dearg (Red Spear), which caused wounds that could not be healed. He used Gáe Dearg and Moralltach for adventures which were matters of life and death, and Gáe Buidhe and Beagalltach for lesser battles.

Diarmuid's father, Donn, was a warrior of the Fianna. At a dinner party, Donn, jealous of the attention given to the son of Aengus' steward, killed the steward's son when no one was looking. Aengus resurrected the steward's son in the form of a boar, but the steward required Fionn to find out the truth and, upon learning the truth, put a curse upon Diarmuid: He was to be killed by the boar, the steward's transformed son.

Diarmuid was famous for his beauty, and for his 'love spot', which made him irresistible to women. While hunting one night he met a woman who was the personification of youth. After sleeping with him she put a magical love spot on his forehead that caused any woman who looked at it to fall in love with him.

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Wikipedia