Admiral Sir William Reginald Hall

28 June 1870 – 22 October 1943

Thanks to intercepts from Room 40, Hall was instrumental in the interception of the steamer Aud on 21 April 1916 by HMS Bluebell, which was carrying German arms to Ireland. The following day the man who had organised the arms shipment, Sir Roger Casement, was arrested in Tralee Bay after disembarking from a German U-Boat. Hall was aware of the upcoming Easter Rising in Dublin, but refused to reveal his sources, so that when information of the rising did reach the government, its authenticity was questioned. Hall interrogated Casement and allegedly refused Casement the opportunity of making a public demand for the cancellation of the uprising.