| Surname | Forename | Rank | Unit | Naval_Service |
| McNULTY | Reginald Walter | Trimmer | H.M.S. "Paxton" | Mercantile Marine Reserve |
| MEDLEY | James | Ship's Cook | S.S. "Lorle" (West Hartlepool) | Mercantile Marine |
| MEEHAN | William | Chief Engine Room Artificer | H.M.S. "Aboukir" | Royal Navy |
| MILLS | Henry Couper | Boy 1st Class | H.M.S. "Indefatigable" | Royal Navy |
| MONKS | James | Leading Seaman | H.M.S. "Indefatigable" | Royal Navy |
| MONKS | John | Seaman | H.M.S. "Marksman" | Royal Naval Reserve |
| MONTGOMERY | Richard Tichborne | Lieutenant | H.M.S. "Redbreast" | Royal Naval Reserve |
| MOONEY | Patrick | Fireman | S.S. "Franconia" (Liverpool) | Mercantile Marine |
| MOORE | Charles Lewis | Lieutenant | H.M.A. Submarine "AE1" | Royal Australian Navy, on loan from Royal Navy |
| MORAN | John | Able Seaman | S.S. "Connaught" (Dublin) | Mercantile Marine |
| MORRIS | Henry James | Fourth Engineer Officer | S.S. "Aburi" (London) | Mercantile Marine |
| MORRISON | Thomas | Able Seaman | S.S. "Duckbridge" (Newcastle) | Mercantile Marine |
| MULCAHY | William George | Fireman and Trimmer | S.S. "Oriole" (London) | Mercantile Marine |
| MULHALL | John Joseph | Signalman | H.M. Submarine "E50" | Royal Navy |
| MULLEN | William | Engineman | H.M. Trawler "Sealark II" | Royal Naval Reserve |
| MURPHY | Bernard | Fireman | S.S. "Leinster" (Dublin) | Mercantile Marine |
| MURPHY | James Edward | Boy 1st Class | H.M.S. "Albion" | Royal Navy |
| MURPHY | Joseph Pierce | Signalman | H.M.S. "Amphion" | Royal Navy |
| MURPHY | Thomas | Fireman | S.S. "W. M. Barkley" (Belfast) | Mercantile Marine |
| MURPHY | William | Fireman | S.S. "Calista" (Glasgow) | Mercantile Marine |
| NAIRN | Francis William | Engineer Lieutenant | | Royal Indian Marine |
| NELSON | T J | Master | Palmella | Mercantile Marine |
| NIVEN | James Douglas | Engineer Lieutenant Commander | H.M.S. "Black Prince" | Royal Navy |
| NYHAN | T | Able Seaman | S.S. "Hazelwood" (Middlesbrough) | Mercantile Marine |
| O'BEIRNE | Ernest Louis | Able Seaman | Hood Battalion, Royal Navy Division | Royal Naval Volunteer Reserve |
| O'BRIEN | Joseph | Leading Stoker | H.M.S. "Dartmouth" | Royal Navy |
| O'BRIEN | Patrick | Able Seaman | H.M.S. "Anchusa" | Royal Navy |
| O'BRIEN | Robert | Petty Officer Stoker | H.M.S. "Drake" | Royal Navy |
| O'CALLAGHAN | Michael | Lamps | S.S. "Umgeni" (London) | Mercantile Marine |
| O'CONNOR | Edward | Seaman | S.S. "Swanmore" (Liverpool) | Mercantile Marine |
| O'CONNOR | Joseph | Second Mate | S.S. "Jutland" (Cardiff) | Mercantile Marine |
| O'CONNOR | Michael | Stoker 1st Class | H.M.S. "Vanguard" | Royal Navy |
| O'KEEFE | James | Fireman | H.M.S. "Louvain" | Mercantile Marine Reserve |
| O'LEARY | Michael Joseph | Private | 1st Royal Marine Battalion, Royal Navy Division | Royal Marine Light Infantry |
| O'NEIL | Michael | Mate | S.V. "Brandon" (Barrow in Furness) | Mercantile Marine |
| O'NEILL | Harry John | Stoker 1st Class | H.M.S. "Mary Rose" | Royal Navy |
| O'REILLY | Frank Power | Lieutenant | H.M.S. "Invincible" | Royal Navy |
| O'TOOLE | Patrick | Fireman | S.S. "Leinster" (Dublin) | Mercantile Marine |
| ORANGE | John | Fireman | S.S. "Lusitania" (Liverpool) | Mercantile Marine |
| PENDER | Patrick | Trimmer | H.M.P.M.S. "Ascot" | Royal Naval Reserve |