On 10 October 1918, the RMS Leinster, a mail and passenger ship operated by the City of Dublin Steam Packet Company, was torpedoed and sunk by the German submarine UB-123 in the Irish Sea. This tragic event occurred during the final weeks of World War I, and it resulted in the loss of 564 lives, marking it as the worst maritime disaster ever recorded in the Irish Sea.
The RMS Leinster was on a routine voyage from Dublin to Holyhead, carrying civilians, military personnel, and mail. The war had made such crossings increasingly dangerous, as German U-boats patrolled the waters around Britain and Ireland. Despite this threat, the ship set sail on the morning of October 10, with over 700 passengers and crew on board.
As the Leinster approached the Welsh coast, UB-123, commanded by Oberleutnant Robert Ramm, fired three torpedoes at the ship. Two of them hit their target, causing catastrophic damage. The first struck the postal compartment, and the second hit the engine room. The ship sank rapidly, leaving many of the passengers and crew little time to escape. Despite efforts to launch lifeboats and assist survivors, the cold waters of the Irish Sea claimed hundreds of lives.
Of the approximately 771 people on board, only about 213 survived. The disaster was a devastating blow to both Ireland and Britain, with the majority of the victims being Irish civilians, British and Irish servicemen, and postal workers. The loss of the RMS Leinster came at a time when peace was on the horizon, with the Armistice of World War I just weeks away.
The sinking of the RMS Leinster is remembered as a significant wartime tragedy, and memorials have been erected in both Dublin and Holyhead to honor the lives lost. The disaster also highlighted the widespread devastation caused by unrestricted submarine warfare during the war, which targeted both military and civilian vessels indiscriminately.
