Two days after the U.S. Senate voted 82 to 6 to declare war against Germany, the U.S. House of Representatives endorses the declaration by a vote of 373 to 50, and America formally enters World War I. When World War I erupted in 1914, President Woodrow Wilson pledged neutrality for the United States, a position that the vast majority of Americans favored. Britain, however, was one of America’s closest trading partners, and tension soon arose between the United States and Germany over the latter’s attempted quarantine of the British Isles. Several U.S. ships traveling to Britain were damaged or sunk by German mines, and in February 1915 Germany announced unrestricted warfare against all ships, neutral or otherwise, that entered the war zone around Britain. One month later, Germany announced that a German cruiser had sunk the William P. Frye, a private American vessel. President Wilson was outraged, but the German government apologized and called the attack an unfortunate mistake.