Video: 'The Sussex Pledge WW1'

(Wednesday, January 31, 1917; during the Atlantic U-boat campaign of World War I) — The German government announced today that its U-Boats would once again be allowed to practice unrestricted warfare against all allied shipping and any neutral ships that crossed into the waters around the British Isles.

Germany’s announcement to rescind the Sussex pledge was the first in a series of events which would lead to the entry of the United States into the First World War.