 After the Armistice with Bulgaria on 29 September ended Bulgaria's participation in the war, Durazzo gained importance to the remaining Central Powers as the main port for supplying their forces fighting in the Balkans.Anticipating this, the Allies put together a force to bombard Durazzo.While the second echelon of the attacking force got into position to bombard the town, "U-29" and sister boat maneuvered to attack.