Dag the Wise
Dag the Wise or Dagr Spaka was a mythological Swedish king of the House of Ynglings (dated to the 4th century by 16th-century historiographer Johannes Magnus). He was the son of Dyggvi, the former king. According to legend, he could understand the speech of birds and had a sparrow that gathered news for him from many lands. When the bird was killed on one of these trips, Dag invaded Reidgotaland (considering the date and location, apparently Gothiscandza), in order to avenge it. There he was ambushed by a thrall and killed.
The earliest two versions based on Ynglingatal, i.e. Historia Norwegiæ and Íslendingabók (see below) say that Dag was succeeded by his sons Alrekr and Eírikr who in their turn were succeeded by Dag's grandson Agne (in Historia Norwegiæ incorrectly called Hogne):
Cui [Dyggui] successit in regnum filius ejus Dagr, quem Dani in quodam vado, quod Sciotanvath vel Wapnavath dicitur, dum passeris injurias vindicare conaretur, publico bello occiderunt. Qui genuit Alrik; hunc frater suus Erikr freno percussit ad mortem. Alricr autem genuit Hogna
His [Dyggve's] son Dag succeeded to his throne; he was killed by the Danes in a royal battle at a ford named Skjotansvad, while he was trying to avenge the violence done to a sparrow. This man engendered Alrek, who was beaten to death with a bridle by his brother, Eirik. Alrek was father to Agne, [...]
Íslendingabók only lists the line of succession: x Dyggvi. xi Dagr. xii Alrekr. xiii Agni. xiiii Yngvi''.
However, in the Ynglinga saga, Snorri Sturluson gives Agne as Dag's son and successor, and the two brothers Alrekr and Eiríkr as his grandsons.
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