The document summarizes the key causes and events of World War 1. It discusses the alliances between European powers that divided them into the Allied and Central Powers. The assassination of Archduke Franz Ferdinand set off a series of escalating events that led major European powers into war on two fronts by 1914. The US initially remained neutral but later joined the Allies in 1917 after German U-boats sank American ships. American involvement helped the Allies win the war within a year. The Treaty of Versailles after WWI failed to achieve lasting peace due to its punitive terms against Germany.