In the early morning of 9 April 1940 a fleet of German ships entered the Oslofjord. The Norwegian artillery delayed the German advance long enough for King Haakon VII and his cabinet to escape to England, but there was no stopping the Nazi blitzkrieg. Norway stood on the cusp of a traumatic five-year occupation whose aftershocks would continue to trouble its national consciousness long after the defeated Germans departed in May 1945.

In a magnificent feat of storytelling, Robert Ferguson tells the extraordinary – and relatively little-known – story of the occupation and its judicial aftermath. He focuses in particular on the Germans' attempt to use a Norwegian Nazi administration under Vidkun Quisling to impose a National Socialist revolution on Norwegians, and on the many brave and ingenious ways in which the Norwegians resisted the attempt.

Ferguson describes the occupation in all its aspects – from Nazi terror to non-violent resistance, from censorship to sabotage – ending with a riveting and heart-rending account of the trial and ensuing execution of a member of the Norwegian resistance. Norway's War presents a series of heterogeneous but interlinked narratives which are richly involving in themselves but which always allow the wider politico-military story to keep moving forward. The key players in the occupation, whether occupiers, collaborators or resisters, both non-violent and otherwise, are memorably characterised. One of them, the remarkable double agent Gunnar Waaler, occupies an especially prominent place in the narrative.

Above all, Norway's War evokes the bravery of ordinary Norwegians in a manner that is deeply engaging, moving and fascinating.