When did World War 1 begin and end? — It began on July 28, 1914, and ended on November 11, 1918.

What were the four main causes of WW1? (MAIN) — Militarism, Alliances, Imperialism, and Nationalism.

What event triggered the start of WW1? — The assassination of Archduke Franz Ferdinand of Austria-Hungary in Sarajevo on June 28, 1914, by Gavrilo Princip.

What were the two main alliance systems in WW1? — The Triple Entente (France, Russia, Britain) vs. the Triple Alliance / Central Powers (Germany, Austria-Hungary, Ottoman Empire).

What was the Schlieffen Plan? — Germany's military strategy to quickly defeat France by invading through Belgium, then turn east to fight Russia. It failed when Belgium resisted and Britain entered the war.

What was trench warfare? — A form of combat where opposing armies dug networks of trenches facing each other. Soldiers lived in these trenches for months, leading to a deadly stalemate on the Western Front.

What was the Western Front? — The main theater of WW1, a line of trenches stretching roughly 700 km from Belgium to Switzerland where France, Britain, and Germany fought.

What was the Battle of the Marne (1914)? — A crucial early battle where Allied forces stopped the German advance into France, turning the war into a stalemate and leading to trench warfare.

What was the Battle of Verdun (1916)? — One of WW1's longest and bloodiest battles between France and Germany. It lasted 10 months and resulted in nearly 700,000 casualties combined.

What was the Battle of the Somme (1916)? — A massive British offensive on the Somme River. On the first day alone (July 1, 1916), the British suffered 57,470 casualties — the bloodiest day in British military history.

What was unrestricted submarine warfare? — Germany's policy of sinking any ship — including neutral vessels — in war zones around Britain. It was a key reason the United States entered the war.

What was the Zimmermann Telegram (1917)? — A secret diplomatic message from Germany to Mexico, proposing a military alliance against the USA. Its interception by Britain helped push America into WW1.

When did the United States enter WW1 and why? — April 6, 1917. Key reasons: unrestricted German submarine warfare (sinking of the Lusitania) and the Zimmermann Telegram.

What was the Lusitania? — A British ocean liner sunk by a German submarine in 1915, killing 1,198 people including 128 Americans. It fueled anti-German sentiment in the USA.

What was the Russian Revolution's impact on WW1? — The 1917 Russian Revolution led to Russia withdrawing from WW1, allowing Germany to move troops from the Eastern to Western Front.

What was the armistice that ended WW1? — An agreement to stop fighting, signed on November 11, 1918, at 11:00 AM. Germany agreed to surrender under the terms set by the Allies.

What was the Treaty of Versailles (1919)? — The peace treaty that officially ended WW1. It blamed Germany for the war (War Guilt Clause), imposed heavy reparations, reduced German territory, and limited its military.

How many people died in World War 1? — Approximately 17–20 million people died — including both military and civilian casualties — making it one of the deadliest conflicts in history.

What was the League of Nations? — An international organization created after WW1 to maintain world peace, proposed by US President Woodrow Wilson. The USA never joined due to Congressional opposition.

How did the Treaty of Versailles contribute to WW2? — The harsh reparations and humiliation imposed on Germany created economic hardship and resentment, helping Adolf Hitler and the Nazi Party rise to power.

What was No Man's Land? — The strip of land between opposing trenches on the Western Front, extremely dangerous and heavily contested, filled with barbed wire and shell craters.

What new weapons were introduced in WW1? — Poison gas, tanks, aircraft (for combat), machine guns, and long-range artillery were all used on a large scale for the first time.

Who were the key leaders of WW1 Allied powers? — France: Georges Clemenceau. Britain: David Lloyd George. USA: Woodrow Wilson. Italy: Vittorio Orlando.

Who led Germany during WW1? — Kaiser Wilhelm II was the Emperor of Germany throughout WW1. General Erich Ludendorff was the key military strategist.

What were Woodrow Wilson's 14 Points? — A proposal by US President Wilson for a peaceful post-war world, including freedom of the seas, self-determination of nations, and the creation of the League of Nations.