Lord Mountbatten, a retired British statesman and cousin to Queen Elizabeth II, was assassinated on 27 August 1979 off the coast of Mullaghmore, Ireland. Thomas McMahon, an Irish republican and a volunteer for the Provisional Irish Republican Army (IRA), planted a bomb on Mountbatten's boat, the cabin cruiser Shadow V, during Mountbatten's annual summer trip to Classiebawn Castle, his house on the Mullaghmore Peninsula.