Ailill (or Oilioll), son of Slánoll, was, according to medieval Irish legend and historical tradition, a High King of Ireland; scholars now believe these kings to be a pseudohistorical construct of the eighth century AD, a projection into the distant past of a political entity which did not become a reality until Maelseachlainn I.
He ruled for twelve, fifteen or sixteen years, according to various versions of the Lebor Gabála Érenn[1] (Geoffrey Keating[2] and the Four Masters[3] agree on sixteen) before he was killed by Sírna Sáeglach, a great grandson of Rothechtaid mac Main.
The Lebor Gabála synchronises his reign with that of Deioces of the Medes (694-665 BC).
The chronology of Keating's Foras Feasa ar Éirinn dates his reign to 831–815 BC, that of the Annals of the Four Masters to 1197–1181 BC.
This biography of a member of an Irish royal house is a stub.