April 9, 1940
April 9 Norge torpedoed at Narvik by German destroyers
April 9 Eidsvold torpedoed at Narvik by German destroyers
Submarine B1 scuttled but later raised and used to escape Norwegian personnel to Britain.
Norwegian campaign
First battle of Narvik 2 German destroyers sunk and a further 2 seriously damaged. Eight merchantmen and the ammunition ship Raunfels also sunk. Two British destroyers sunk in return.
April 13 and 14 two submarines lost around Narvik and Harstad one U-64 sunk April 13 by a float plane from Warspite the other U-49 sunk by Warspite's escorts 14 April.
April 13 second battle of Narvik all 8 German destroyers wiped out by a force including Warspite, 9 destroyers and planes from the carrier Furious.
The lost destroyers were the Z2 George Thiele, Z9 Wolfgang Zenker, Z11 Bernd von Arnim, Z12 Erich Giese, Z13 Erich Koeller, Z17 Diether von Roeder, Z18 Hans Lumann, Z19 Herman Kunne, Z21 Anton Schmitt, and Z22 Wilhelm Heidkamp.
April 13, 1940
April 13 and 14 two submarines lost around Narvik and Harstad one U-64 sunk April 13 by a float plane from Warspite the other U-49 sunk by Warspite's escorts 14 April.
Second battle of Narvik all 8 German destroyers wiped out by a force including Warspite, 9 destroyers and planes from the carrier Furious.
The lost destroyers were the Z2 George Thiele, Z9 Wolfgang Zenker, Z11 Bernd von Arnim, Z12 Erich Giese, Z13 Erich Koeller, Z17 Diether von Roeder, Z18 Hans Lumann, Z19 Herman Kunne, Z21 Anton Schmitt, and Z22 Wilhelm Heidkamp.
Narvik campaign
British losses around Narvik in April 1940
April 10 two British destroyers lost, the Hunter sunk and the Hardy run aground in the first battle of Narvik, two other destroyers badly damaged.
April 13 destroyer Eskimo loses her bow in the second battle of Narvik.
Destroyer HMS Jaguar bombed during evacuations in late May.
Sub losses off Norway
| April | Thistle, Tarpon, Startlet |
| May | Seal, Orzel(Po) |
| June | 0.13(Du) |
| July | Shark, Salmon, Thames, Narwhal |
| August | Spearfish |
Thistle was sunk by U-4 on April 10. Tarpon lost 14 April, Seal mined May 4, captured by a German plane and trawler, Salmon was lost between 4-7 July. Narwhal lost between 22-28 July, Spearfish was sunk by U-34 August 1, though was not reported missing for several days. Thames was a river class submarine.