'Halfback' (i) was a British naval sweep by the light cruiser Mauritius and light anti-aircraft cruiser Diadem of Admiral Sir Henry Moore’s Home Fleet against shipping off the coast of German-occupied Norway (27/28 January 1945).

This so-called Action of 28 January 1945 was an inconclusive action between the two British cruisers and three German destroyers off the Norwegian coastal city of Bergen. This was both the last of many actions fought between British and German warships off Norway during the war and the penultimate surface engagement fought by the Germans, the last taking place on 18 March 1945 when a force of two torpedo boats and a destroyer was defeated by two British destroyers in the Battle of the Ligurian Sea.

Shortly after 24.00 on the night of 27/28 January, as the three destroyers of Kapitän Hugo Freiherr von Wangenheim’s 4^th Zerstörer-Flottille were steaming from northern Norway to the Baltic Sea, they were intercepted by Mauritius and Diadem. In the resulting action the destroyers Z 31 and Z 34 were damaged by gunfire but the German flotilla outran the slower British ships and escaped. All the German warships eventually reached the Baltic, though Z 31 was delayed until repairs had been completed in Norway.

The 4^th Zerstörer-Flottille at this time comprised the 'Narvik' class destroyers Z 31, Z 34 and Z 38. By January 1945, these ships had been stationed in northern Norwegian waters for three and a half years, but had only occasionally put to sea during 1944. As a result of Germany’s steadily worsening strategic situation, the flotilla was ordered in January to leave Norwegian waters and return to the Baltic, and the three destroyers departed Tromsø on 25 January.

The Home Fleet’s ships undertook a number of attacks on German shipping off the coast of Norway during January 1945. These included successful attacks by motor torpedo boats on three escorted ships between 6 and 8 January, and the interception of a convoy by the heavy cruiser Norfolk and the light anti-aircraft cruiser Bellona near Egersund on the night of 11/12 January.

On 27 January, the escort carriers Campania, Nairana and Premier departed the Home Fleet’s main base at Scapa Flow on the 'Winded' raid against shipping near Vaagsø. The carriers were escorted by the heavy cruiser Berwick and six destroyers.

The British were alerted to the movement of the 4^th Zerstörer-Flottille by 'Ultra' signals intelligence, Moore being informed that the destroyers had sailed on 27 January, shortly after the three carriers and their escort had put to sea. He believed that the German ships were likely to use the Leads (the route between the coastal islands and the shore) as was common for the Kriegsmarine. If this route was used, it would be preferable for an attack to be made by the aircraft of Air Vice Marshal S. P. Simpson’s No. 18 Group RAF as Norway’s inshore waters were protected by naval mines and coastal batteries. Alternatively, the German ships might make a high-speed night passage outside of the coastal islands, against which eventuality Moore ordered Vice Admiral Frederick Dalrymple-Hamilton, commanding the 10^th Cruiser Squadron, to sail with Mauritius and Diadem for a patrol off Bergen. The Home Fleet had no destroyers available to accompany Dalrymple-Hamilton’s force, and Moore considered but decided against cancelling the carrier operation in order to free some of these ships.

Contrary to British expectations, von Wangenheim opted to take the faster route in the more open waters outside the coastal islands. During the evening of 27 January the destroyers were spotted and attacked by British aircraft to the west of Sognefjord, but continued their voyage. Contact was made between the two naval forces at 00.48 on 28 January. At this time, the 4^th Zerstörer-Flottille was heading to the south and was about 15 miles (24 km) to the south-west of the Utvær lighthouse and 35 miles (55 km) to the north-west of Bergen in a calm sea with excellent visibility under a full moon.

The British and German forces spotted each another simultaneously as the the cruisers were about 11 miles (18 km) west of the destroyers. On sighting the destroyers, the British ships fired star shells to illuminate the area and turned to the south onto a course parallel with that of the German ships. Z 31 suffered extensive damage early in the action: she was hit by seven 6-in (152-mm) shells, which set her on fire, damaged her hydrophone compartment and torpedo transmitting stations, and destroyed her forward gun turret. The destroyer’s speed was not affected, but her casualties were heavy, with 55 men killed and another 24 wounded.

After Z 31 had been damaged, Korvettenkapitän Karl Hetz on board Z 34 assumed command of the 4^th Zerstörer-Flottille and Z 34 made two torpedo attacks on the British cruisers in an attempt to force them to change course, but had no success. Z 38 also tried to launch torpedoes, but had to break off this attack when her funnel caught fire and one of her boiler tubes burst. Z 34 suffered a hit on her waterline during this period. After Z 34 had been damaged, Hetz decided to turn to the north and attempt to outrun the British cruisers. Z 34 fired a third torpedo salvo as the flotilla made this turn, again without result, and the three ships laid smoke screens in an attempt to conceal their position. The two cruisers also turned to the north to chase the German ships, and this led to a running battle in which Mauritius sustained a hit on her mess deck that caused no casualties, and six minutes later Diadem was struck on her boat deck by a shell that killed one man and wounded three more.

The German destroyers were capable of 38 kt, while Diadem and Mauritius could reach only 32 and 31 kt respectively, so the destroyers gradually pulled ahead and came under the protection of shore batteries at about 02.00. The British ships broke off the pursuit and returned to Scapa Flow after the guns fired on them.

Early in the morning of 28 January, the 4^th Zerstörer-Flottille resumed its passage and entered the harbour of Bergen. Z 31 moved into dock for repairs, and Z 34 and Z 38 departed on the evening of 28 January. The two ships came under air attack on the following day, but suffered no damage and sheltered in a fjord to the south of Stavanger during daylight hours. They put to sea again on the evening of 29 January and reached Kiel on 1 February.

At Bergen Z 31 received initial repairs, which included removing the wreckage of her forward turret, and departed on 8 February for Horten. Here she received further repairs and had her anti-aircraft armament upgraded. Her forward turret was not replaced, but a 105-mm (4.13-mm) gun was shipped in its place. This was intended as a temporary measure but remained for the rest of the destroyer’s career. After the completion of these repairs, Z 31 reached Gotenhafen on 15 March.

The last German destroyer remaining in northern Norwegian waters, Z 33 sailed for Germany on 5 February but ran aground en route and suffered further damage in an Allied air attack on 9 February, when massed Allied efforts resulted in the sinking of many German ships and the damaging of still more. Following repairs, the destroyer arrived at Swinemünde on 2 April. By this time most of Germany’s remaining warships were stationed in the Baltic Sea, where they supported German military operations and the evacuation of civilians until the end of the war on 8 May.