From 1914 until 1917, submariners from Britain and Russia fought against the German Imperial Navy for control of the sea lanes in the icy Baltic. Their endeavors have been buried beneath the stories of Second World War U-boats, but with a serendipitous mistake in Kew Archives, a water damaged, blood stained submarine log landed in front of Dr Ian Johnson. Thus began a mission to uncover the story of British submarine strategy in the First World War. Ian is Professor of Military History at the University of Notre Dame. In this episode he shares the story of the British submariners, the role of the Russian revolution in the Baltic and how this theatre of the First World War impacted upon the Second.