E. Cobham Brewer 18101897. Dictionary of Phrase and Fable. 1898.
Hurrah,
the Hebrew \??\ Our Old Hundredth Psalm begins with Shout joyfully [hurrah] to Jehovah! The word is also of not uncommon occurrence in other psalms. See Notes and Queries, October 16th, 1880. (Norwegian and Danish, hurra!) (See HUZZA.)
1
The Norman battle-cry was Ha Rollo! or Ha Rou! (French, huzzer, to shout aloud; Russian, hoera and hoezee.)
2
The Saxon cry of Out! Out, Holy Crosse! rose high above the Norman sound of Ha Rou! Ha Rou, Notre Dame!Lord Lytton: Harold, book xii. chap. 8.
Wace (Chronicle) tells us that Tur aie (Thor aid) was the battle cry of the Northmen.