A detailed account of Germany’s groundbreaking Operation Weserübung, the first three dimensional—land, sea, air—strategic invasion in history. The German invasion of Denmark and Norway in April 1940 brought a sudden and shocking end to the “Phoney War” in the West. In a single day, multiple seaborne and airborne landings established German forces ashore in Norway, overwhelming the unprepared Norwegian forces and catching the Allied Powers completely by surprise. Their belated response was ill-thought-out and badly organized, and by June 9 all resistance had formally ended. The strategic importance of Scandinavian iron ore, shipped through the port of Narvik to Germany, was the main cause of the campaign. The authors show how Allied attempts to interdict these supplies provoked German plans to secure them, and also how political developments in the inter-war years resulted in both Denmark and Norway being unable to deter threats to their neutrality despite having done so successfully in the First World War. The German attack was their first “joint” air, sea, and land operation, making large-scale use of air-landing and parachute forces, and the Luftwaffe’s control of the air throughout the campaign would prove decisive. Although costly, particularly for the Kriegsmarine, it was a triumph of good planning, improvisation and aggressive, determined action by the troops on the ground. Making full use of Norwegian, Danish, and German sources, this book is a full and fascinating account of this highly significant campaign and its aftermath both for the course of the Second World War and the post-war history of the two countries conquered with such unprecedented speed.