In WWI under a crippling naval blockade of its North Sea ports which ultimately resulted in the starvation of thousands of its citizens and as land warfare in Europe drags on, Germany endeavours to counter-blockade Britain via U-boat attacks on shipping and by mining waters round the British Isles. Hundreds of fishing vessels from every port and harbour in Britain are pressed into minesweeping duties and minelayers sow fields to restrict and destroy German vessels. Their efforts allow the powerful Royal Navy to hold the German Navy in port -- except for occasional skirmishes, including the Battle of Jutland. American destroyers hunt U-boats in British waters, while minelayers create a barrier between the Orkney Islands and Norway, to try to deny the enemy entry into the Atlantic. Desperate, Germany mounts a U-boat offensive off North America in the summer 1918, to induce the U.S. to bring her destroyers home. Although nearly one hundred vessels are sunk, this action fails. Germany surrenders in late autumn 1918 and allied vessels are left with the deadly task of removing thousands of mines laid in the war. One hundred and fifty photographs, maps, and diagrams; appendices; and an index to full-names, places and subjects add value to this work.