On 6 April 1917, the United States formally declared war on Germany, entering World War I on the side of the Allied Powers.
The declaration followed President Woodrow Wilson’s address to Congress, citing German unrestricted submarine warfare and the Zimmermann Telegram as unacceptable provocations.
The US entry significantly bolstered Allied strength and morale, providing crucial military and economic support that would help shift the balance of the war in favour of the Allies.
