The manor of Sherfield Upon Loddon was held by the English Crown till the reign of Henry II, by whom it was granted, before 1167-8, to his marshal William Fitz Aldelin on his marriage with Juliane.
In 1173 Pope Adrian's bull granting the kingdom of Ireland to Henry, Laudabiliter, was entrusted to the prior of Wallingford and him to exhibit before the synod of bishops at Waterford.
On the death of Strongbow, Lord of Leinster, in 1176, the king appointed him deputy over the whole of that kingdom and granted him the wardship of Isabel, the earl's daughter and heir.
His government, which is represented as having been weak and negligent, did not last above a year, Prince John receiving a grant of the Lordship of Ireland at the parliament held at Oxford in May 1177, Fitz-Aldelm himself being present there.
During his residence in Ireland, he founded the priory of Saint Thomas the Martyr at Dublin; and in Henry's charter of confirmation he is called the king's "dapifer" (steward).