Aare, Diederik (Dirk Or Thierry) Van Der,
was bishop of Utrecht in the 13th century. He seems to have attended more to the temporalities of his see than to his spiritual duties, and was involved in frequent warfare with William, count of Holland. He governed Utrecht for fourteen years, and died at Deventer, Dec. 5, 1212. See Hook, Eccles. Biog. s.v.