WW1 At Sea

WWI: The War at Sea

Careful Moves

  • The naval war was characterized by caution from both sides.

  • The British Navy focused on a blockade of Germany after clearing enemy shipping from European waters.

  • Germany initially used torpedoes and underwater mines to weaken the British navy but shifted to attacking British merchant ships with U-boats.

  • Location Significance:

    • Britain's proximity to German trade routes significantly reduced German trade early in the war.

    • Germany and Austria-Hungary could not utilize 61% of its trading ships, impacting their war effort.

    • Britain laid underwater mines in German shipping areas to hinder their trade.

Unterseeboot (U-Boats)

  • Before the war, submarines were not considered a primary weapon against merchant ships.

  • In 1914, Germany had only 28 U-boats but began a war zone declaration around Great Britain.

  • Any ships (military or civilian) within this zone were subject to attack.

  • This policy eventually regrettably backfired for Germany.

Sinking of Ships

  • Hundreds of neutral ships were sunk, raising concerns over the escalation of conflict


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Attacking Neutral Ships

  • By 1915, German U-boats sank 120,000 tons of goods from Allied and neutral nations, including American ships.

  • The sinking of the ocean liner Arabic (August 19, 1915) killed 40, including 3 Americans, prompting a strong US protest.

  • Germany promised to halt torpedo attacks on passenger ships, opting to use gunfire instead, a largely superficial compliance to diplomacy.

Unrestricted Submarine Warfare

  • In 1917, Germany planned a full assault on Allied and neutral shipping to effectively starve Britain into submission, thus risking American involvement.

  • This led to American ships being targeted, inciting outrage in the US.

  • The Convoy System became crucial for protecting merchant ships, involving armed ships escorting them across the ocean and maintaining essential supply lines.


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Importance of Trade

  • Trade across the ocean was vital for Britain’s survival, particularly for food and supplies during the war.

  • The convoy system significantly reduced losses from U-boat attacks, thereby supporting the British war effort.

America Enters the War

  • Initially, the US sought to remain neutral, focusing on trade with Britain for economic benefit. However, ongoing attacks on US ships shifted sentiment towards war.

  • The sinking of the Lusitania in 1915, carrying 1,962 passengers, including 128 Americans, prompted outrage after it sank from a U-boat attack.

  • Key figures, such as millionaire Alfred Vanderbilt, were among the American casualties, exacerbating tensions.


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Planned War with Mexico

  • A intercepted German communication in January 1917 revealed a plan to persuade Mexico to wage war against the US.

  • Germany promised military backing and the restoration of territories lost to the US (Texas, New Mexico, Arizona).

  • This escalated US anger leading to their declaration of war in April 1917, joining the Allies in the conflict.

Key Terms

  • Blockade: Preventing movement of goods or forces across land and water.

  • Merchant Ships: Non-military vessels for transporting goods.

  • Neutral: States unaligned politically in military alliances.

  • Ocean Liner: Large passenger ships.

  • Convoy System: Military protection for merchant ships against U-boat attacks.

American Involvement

  • By 1918, the US was sending around 10,000 troops daily to France, hastening Germany's defeat.