Sitric was a member of the Norse dynasty which had ruled Dublin from the middle of the ninth century until 902. In that year the Ivar II, King of Dublin, and his family were driven from the city by Cerball mac Muirecáin Ó Fáeláin the King of Leinster and Máel Finnia mac Flannacáin the King of Brega. In the "Annals of Ulster" Sitric Caech and Ívarr II are both referred to as "ua Ímair", "grandson of Ímar", a reference to Ivar I, who was the King (or co-regent) of Dublin from about 853 until his death in 873 and the ancestor of most of the Norse rulers of the city. Sitric, therefore, was either a brother or a first cousin of the ousted Ivar II (who had died in Scotland in 904). It is probably safe to assume that he was born in Dublin and was a young man when he and his family fled for their lives in 902.