page_title: List of submarine actions
section_title: World War I
hierarchical_section_title: List of submarine actions / Actions / World War I
caption_attribution_description: Deutsch: Versenkung der britischen Panzerkreuzer CRESSY, HOGUE und ABOUKIR durch U 9 am 22. September 1914 vor der niederländischen Küste. Nach einer Originalzeichnung von Hans Bohrdt
context_page_description: 1864, February 17 – Confederate human-powered submarine H. L. Hunley sinks the Union sloop USS Housatonic with spar torpedo, off Charleston. The H. L. Hunley thus became the first submarine to successfully sink an enemy vessel in combat, and was the direct progenitor of what would eventually become international submarine warfare.
context_section_description: 1914, September 5 – HMS Pathfinder is sunk at the start of World War I by U-21, becoming the first ship to ever be sunk by a self-propelled torpedo fired by submarine.
  1914, September 22 – German submarine U-9 sinks three unescorted British armoured cruisers HMS Aboukir, HMS Hogue and HMS Cressy in approximately one hour.
  1914, October 18 – German submarine U-27 sinks HMS E3 in the first ever successful attack on one submarine by another.
  1914, October 20 – German submarine U-17 sinks SS Glitra in the first submarine sinking of a merchant ship during the world wars.
  1915, May 7 – German submarine U-20 sinks RMS Lusitania killing 1,198 and leaving 761 survivors.  The sinking turned public opinion in many countries against Germany, contributed to the U.S. entry into World War I.
  1915, May 25/27 – In the morning of May 27 German submarine U-21 sinks the British pre-dreadnought battleship HMS Majestic off the Gallipoli peninsula. Two days after the same U-boat sunk the pre-dreadnought HMS Triumph near Gaba Nepe.
  1916, March 22 – German submarine SM U-68 is sunk by the Q-ship – a merchant ship carrying hidden weapons – HMS Farnborough in the first successful use of depth charges. (Farnborough sank the SM U-83 in 1917)
caption: Illustration by Hans Bohrdt depicting the sinking of HMS Cressy, HMS Hogue and HMS Aboukir by U-9 on 22 September 1914 off the Dutch coast.
exif: {}