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The Eastern Front of World War II was a theatre of conflict between the European Axis powers and co-belligerent Finland against the Soviet Union, Poland and other Allies, which encompassed Central Europe, Eastern Europe, Northeast Europe, and Southeast Europe from 22 June 1941 to 9 May 1945.
From the outbreak of war with Napoleonic France, Britain had enforced a naval blockade to choke off neutral trade to France, which the US contested as illegal under international law. To man the blockade, Britain pressed American merchant sailors into the Royal Navy.
U-boat is an anglicised version of the German word U-Boot [ˈuːboːt] (About this soundlisten), a shortening of Unterseeboot, literally "undersea boat".
RMS Lusitania was a British ocean liner that was sunk on 7 May 1915 by a German U-boat 11 miles off the southern coast of Ireland, killing 1,198 passengers and crew. The sinking presaged the United States declaration of war on Germany.
The Zimmermann Telegram was a secret diplomatic communication issued from the German Foreign Office in January 1917 that proposed a military alliance between Germany and Mexico. If the United States entered World War I against Germany, Mexico would recover Texas, Arizona, and New Mexico.
A declaration of war is a formal act by which one state goes to war against another. The declaration is a performative speech act (or the signing of a document) by an authorized party of a national government, in order to create a state of war between two or more states.
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