The sinking Motion_directional of the Cunard ocean liner RMS `` Lusitania '' occurred Coming_to_be on Friday , 7 May 1915 during the First World War , as Germany waged submarine warfare Hostile_encounter against the United Kingdom which had implemented Action a naval blockade of Germany .

`` Lusitania '' fell Motion_directional victim to torpedo attack relatively early in the First World War , before tactics for evading Escaping submarines were properly implemented Action or understood .