Join David Snook as he looks at the submarine war fought around Ireland in the last two years of World War One. The endgame began with the German move to unrestricted submarine warfare in February 1917 which brought the USA into the war. The U-boats targeted the supply chain of British merchant ships. From September 1918 their multinational crews were issued with an identity card which included a passport style photo. One in fifteen of this workforce was Irish. David will use the archive to develop his story and its impact on Dublin port.