According to a saga included in the Fragmentary Annals of Ireland, material of uncertain reliability, Auisle was a younger brother of Amlaíb and Ímar. Whether brothers or not, the evidence of the Irish annals associates Auisle, Amlaíb and Ímar. Auisle is first noticed in the Irish annals in 863 when, along with Amlaíb and Ímar, he led an army to plunder the pre-historic tombs of Brú na Bóinne.
Auisle is not again mentioned until 866, at which time he joined Amlaíb on an expedition to north Britain, while Ímar appears to have joined the Great Heathen Army in Mercia, East Anglia and Northumbria. Auisle and Amlaíb ravaged Fortriu and all Pictland, taking hostages and remaining over the winter.
Amlaíb returned alone to Ireland in 867, for the Annals of Ulster say that "Auisle, one of three kings of the heathens, was killed by his kinsmen in guile and parricide". The saga in the Fragmentary Annals expands on this, stating that Auisle was killed by Amlaíb in a quarrel over Amlaíb's wife. This wife was said to be a daughter of Cináed, although whether this is intended to mean Cináed mac Ailpín, king of the Picts, Cináed mac Conaing, king of Brega, or some other, more obscure Cináed, is uncertain.
The only descendant of Auisle identified in the records appears to be an unnamed son who was killed in 883, reported by the Annals of Ulster as the "death of Auisle's son at the hands of Iergne's son and the daughter of Mael Sechnaill". The much later Chronicon Scotorum glosses this, stating that it was Ottár son of Járnkné, possibly identical with Ottir Iarla, and Muirgel daughter of Máel Sechnaill mac Máele Ruanaid who arranged the killing, but no motive is given.
Auisle was later the name of a grandson (died circa 1012) of Ivar of Limerick.
- No Old Norse sources name Auisle, and Ásl is preferred. The name probably appears in Old English as Eowils.
- Amlaíb is sometimes identified with Olaf the White and Ímar with Ivar the Boneless, but sagas are unreliable sources for the ninth century; Woolf, Pictland to Alba, pp. 277–285. Other sources name a fourth brother, Hálfdan; Downham, Viking Kings, pp. 15–16; Hudson, "Óláf".
- Downham, Viking Kings, pp. 20 & 246; Woolf, Pictland to Alba, p. 108; Hudson, "Óláf"; Costambeys, "Ívarr".
- Downham, Viking Kings, pp. 21, 139 & 246; Hudson, "Óláf".
- Costambeys, "Ívarr"; Downham, Viking Kings, p. 21.
- Woolf, Pictland to Alba, pp. 108–109; Downham, Viking Kings, pp. 139–140.
- Woolf, Pictland to Alba, pp. 108–109; Downham, Viking Kings, pp. 140–141 & 246; Hudson, "Óláf", presumes Amlaíb's wife to have been a daughter of Cináed mac Conaing.
- Downham, Viking Kings, pp. 25, 257, 263 & 266.
- Costambeys, Marios (2004), "Ívarr (d. 873)", Oxford Dictionary of National Biography, retrieved 2007-10-25
- Downham, Clare (2007), Viking Kings of Britain and Ireland: The Dynasty of Ívarr to A.D. 1014, Edinburgh: Dunedin, ISBN 978-1-903765-89-0
- Hudson, Benjamin (2004), "Óláf the White (fl. 853–871)", Oxford Dictionary of National Biography, retrieved 2007-10-25
- Woolf, Alex (2007), From Pictland to Alba, 789–1070, The New Edinburgh History of Scotland, Edinburgh: Edinburgh University Press, ISBN 978-0-7486-1234-5