'Ostfront' was the German naval undertaking against the JW.55B and RA.55A convoys covered by the British 'FV', and leading to the Battle of the North Cape (25/26 December 1943).

Since August 1941, the Allies had run maritime convoys from the UK and Iceland to the northern ports of the USSR to provide essential supplies for the Soviet war effort on the Eastern Front. These convoys endured much hardship, from both the weather and sea conditions and the frequent attacks to which they were submitted by German naval and air forces stationed in occupied Norway. A key concern was the presence of German capital ships such as the battleship Tirpitz and the battle-cruiser Scharnhorst. Even the threat of these ships' presence was enough to cause disastrous consequences for the convoys, such as that of the PQ.17 convoy that was scattered and mostly sunk by German forces after false reports that Tirpitz had sailed to intercept it. To protect against the threat of Germany’s capital ships in the Arctic and to escort convoys with a high level of success, the Royal Navy had to maintain and deploy great assets that might have been of signal use in other theatres.

'Ostfront' was an attempt by the Germans to intercept the expected Arctic convoys. Late in December 1943, there was the JW.55B Russia-bound convoy comprising 19 cargo vessels under the command of its commodore, retired Rear Admiral Maitland Boucher, accompanied by a close escort of two Canadian destroyers, Huron and Haida, among others, and an ocean escort of eight Home Fleet destroyers led by Onslow. Also in the area was the RA.55A convoy returning from the USSR to the UK and comprising 22 cargo ships, accompanied by a close escort of two destroyers and four other vessels, and an ocean escort of six Home Fleet destroyers led by Milne. It had arrived safely at Murmansk with its normal escorts and the additional protection by Force 1, commanded by Vice Admiral R. L. Burnett, consisting of the light cruiser Belfast (flagship), the heavy cruiser Norfolk and the light cruiser Sheffield.

Escort of the convoys to the USSR was the responsibility of the Home Fleet and its commander, Admiral Sir Bruce Fraser. Fraser wished to neutralise Scharnhorst as she was a major threat to the convoys, and planned a confrontation over the Christmas period of 1943 in which the JW.55B convoy would be used as the 'bait' with which to entice the Germans to sortie. Fraser hoped, and indeed expected, that Scharnhorst would attempt to attack the JW 55B convoy. At a conference of the captains of his force’s ships, Fraser outlined his plan to intercept Scharnhorst at a position between the convoy and the German ship’s Norwegian base. He would then approach the German capital ship to within 12,000 yards (10975 m) in the Arctic night, illuminate Scharnhorst with star shells, and open fire using radar-directed gun fore.

The JW.55B convoy had departed Loch Ewe on the north-west coast of Scotland on 20 December, and was sighted two days later by a Luftwaffe aeroplane, which then shadowed and reported it. By 23 December it was clear to the British from intelligence reports that the convoy had been sighted and was being shadowed from the air. Fraser then put to sea with Force 2 consisting of his flagship, the battleship Duke of York, the light cruiser Jamaica and the destroyers Savage, Scorpion, Saumarez and Free Norwegian Stord. Fraser was anxious not to discourage Scharnhorst from leaving her base, and thus did not approach before it was necessary to do so. As the JW.55B convoy and its escorts approached the area of greatest danger on 23 December, steaming slowly to the east some 250 miles (400 km) off the coast of northern Norway, Burnett and Force 1 set out westward from Murmansk while Fraser with Force 2 approached at moderate speed from the west. On 25 December, Scharnhorst, commanded by Kapitän Fritz Hintze, and the destroyers Z 29, Z 30, Z 33, Z 34 and Z 38 of Kapitän Rolf Johannesson 4^th Zerstörer-Flottille departed the Altafjord under the overall command of Konteradmiral Erich Bey. Scharnhorst set course for the convoy’s reported position as a south-westerly gale developed.

Bey planned to effect the interception of the Allied convoys. With the die thus cast on 25 December, a patrol line of eight U-boats was extended to the south from a point to the west of Bjørnøya, mid-way between the Spitsbergen islands group and northern Norway, and the Luftwaffe began to scour the area with its long-range aircraft.

At the time Fraser and Burnett were informed by the Admiralty that Scharnhorst was at sea, the JW.55B convoy was steaming to the east-north-east at a location just to the south of Bjørnøya at 04.00 on 26 December, with Fraser’s force steaming to the north-east at a position some 210 miles (340 km) to the south-west and Burnett’s force steaming to the south-west some 150 miles (240 km) to east of the convoy, whose safety was Fraser’s primary concern. The German squadron was heading north into a point between the converging courses of the two British forces, and the destroyers were finding it difficult to keep up with Scharnhorst in the sea and weather conditions, which were deteriorating severely.

First sighted three days earlier by a Luftwaffe aeroplane, the JW.55B convoy of 19 laden ships was escorted by the destroyers Impulsive, Onslow, Onslaught, Orwell, Scourge and Canadian Haida, Huron and Iroquois, and the minesweeper Gleaner, under the command of Captain I. M. R. Campbell. When their aerial reconnaissance reported the JW.55B convoy as '40 troop transports', the Germans assumed that a major 'zone of destiny' assault on their positions in northern Norway was imminent. This estimate was later revised, the Germans appreciating that the sighting was more probably of a normal Arctic convoy with a strong escort (in fact 14 destroyers).

Also in the area on passage from the northern USSR to the UK was the RA.55A convoy of 23 unladen ships, of which one turned back, escorted by the destroyers Ashanti, Matchless, Meteor, Milne, Musketeer, Opportune, Virago and Canadian Athabaskan, and minesweeper Seagull, under the command of Captain J. A. McCoy.

Unknown to the Germans, however, was the presence in the area of a considerably more potent British naval element provided by Fraser’s Home Fleet.

The escort of convoys to and from the northern ports of the USSR was the responsibility of the Home Fleet, whose commander, Fraser, wished to neutralise Scharnhorst as her mere existence represented a major threat to the convoys. Fraser therefore planned his own confrontation at the end of the year with JW.55B convoy used as 'bait' to entice the Germans ships from their well protected northern Norwegian lair. The previous JW.55A convoy had arrived safely at Murmansk with its normal escorts and additional protection from Force 1 commanded by Burnett flying his flag in the light cruiser Belfast with the heavy cruiser Norfolk and light cruiser Sheffield.

Fraser hoped, and indeed expected, that Scharnhorst would seek to attack the JW.55B convoy. At a conference of the captains of his force’s ships, Fraser described his plan to intercept Scharnhorst in a position between the convoy and the Germans' Norwegian base before closing the German ship to a range of less than 12,000 yards (10975 m) in the darkness of the long Arctic night, illuminating the battle-cruiser with star shells, and opening fire on the basis of fire-control radar.

The JW.55B convoy had departed Loch Ewe on 20 December, and by 23 December it had become clear from intelligence reports that the convoy had been sighted and was being shadowed by German aircraft. Fraser then put to sea with Force 2, comprising his flagship, the battleship Duke of York, the light cruiser Jamaica, and the destroyers Saumarez, Savage, Scorpion and Free Norwegian Stord. Fraser was anxious not to discourage Scharnhorst from leaving her base, and thereby maintained his position well to the offing but readied everything to make a rapid approach when its became necessary to do so.

As the JW.55B convoy and its escorts approached the area of greatest danger later on 23 December, steaming at low speed and in a position some 250 miles (400 km) off the coast of northern Norway, Burnett’s Force 1 set out to the west from Murmansk while Fraser’s Force 2 approached at moderate speed from the west. Scharnhorst departed her Altafjord base during the evening of 25 December and set course for the convoy’s reported position as a south-westerly gale developed.

On 26 December, in heavy seas and weather so poor that the Luftwaffe could provide little in the way of aerial reconnaissance to aid him, Bey was unable to locate the convoy. Coming to the conclusion that his force had steamed to the north of the convoy, Bey detached his destroyer force to fan out in a search to the south-west and thereby increase the area which could be searched. Meanwhile Fraser, preparing for a German attack, had diverted the returning RA.55A convoy of unladen ships away to the north, out of the area in which the Germans might expect it to be, and ordered the JW.55B convoy to reverse course, to allow him to close. He later ordered four of the destroyers escorting the RA.55A convoy, namely Matchless, Musketeer, Opportune and Virago, to detach and join his Force 2.

Now without escort, Scharnhorst encountered Burnett’s Force 1 just before 09.30 and, at a range of nearly 13,000 yards (11885 m), the British cruisers opened fire with their 8- and 6-in (203- and 152-mm) guns, Scharnhorst responding with salvoes of her own 280-mm (11-in) guns. The German battle-cruiser scored no hits on the cruisers, but the cruisers hit the German ship twice, one shell destroying her radar controls and leaving Scharnhorst virtually blind in a mounting snowstorm. Without radar, the gunners of the German battle-cruiser were forced to aim at the muzzle flashes of the British ships' guns. This was made more difficult for the Germans by the fact that two of the two modern British cruisers were using a new flashless propellant, leaving the older Norfolk the relatively easier target. Believing he had engaged a battleship, Bey turned to the south in an attempt to distance himself from the pursuers and perhaps draw them away from the convoy.

Once he had shaken off his pursuers, Bey turned to the north-east in an attempt to circle round the British warships, but instead of giving chase in sea conditions which limited his cruisers' speed to 24 kt, Burnett had positioned his Force 1 to protect the convoy. It was a decision about which he had some doubts and for which he later received a measure of criticism, but Burnett was supported by Fraser. To Burnett’s relief, shortly after 12.00 Scharnhorst approached the cruisers once more. As the ships once again started to exchange fire, Scharnhorst scored hits on Norfolk, disabling one of her turrets and also her radar. Following this exchange, Bey decided to return back to the Altafjord, and at much the same time ordered the destroyers to attack the convoy at the position in which it had been reported by a U-boat. In fact the position reported was out of date, and as a result the destroyers missed the convoy.

Scharnhorst steamed to the south for several hours. Burnett pursued, but Sheffield and Norfolk each suffered engine problems and dropped back, leaving Belfast dangerously exposed for a time. Scharnhorst's lack of serviceable radar prevented the Germans from taking advantage of the situation, however, allowing Belfast to reacquire the German ship on her own radar and report accordingly.

Meanwhile, Duke of York and her four escorting destroyers were already pressing ahead in an effort to get into position to make a torpedo attack. Fraser had already been informed of Belfast's contact, and the ships of Group 2 themselves soon detected Scharnhorst on radar at 16.15 and began to manoeuvre to bring their full broadsides to bear. It was at 16.17 that Scharnhorst was detected by Duke of York's Type 273 surface-search radar at a range of 45,500 yards (41605 m), and by 16.32 the British battleship’s Type 284 gunnery radar indicated that the range had closed to 29,700 yards (27160 m).

At 16.48, Belfast fired star shells to illuminate Scharnhorst which, wholly unprepared and with her turrets trained fore and aft, was clearly visible from Duke of York. The British battleship opened fire at a range of 11,920 yards (10900 m) and scored a hit with her first salvo, disabling Scharnhorst's two forward turrets, while another salvo destroyed the battle-cruiser’s floatplane hangar. Bey turned to the north in an effort to open the range and escape, but was engaged by the cruisers Norfolk and Belfast, and therefore turned to the east at 31 kt.

In this manner Bey was able to put a greater distance between Scharnhorst and the British ships to increase his prospects of success, and Scharnhorst also put two 280-mm (11-in) shells through Duke of York's masts, severing all the radio antennae and, more seriously, the wires connecting the antenna with the Type 284 gunnery radar. A junior officer climbed the mast and managed to repair the broken wires, but these hits could not have been known to Bey, and his ship’s fortunes became radically worse at 18.20 when a shell fired by Duke of York at extreme range pierced her armour belt and destroyed the No. 1 boiler room. Scharnhorst's speed quickly dropped to a mere 10 kt, and though immediate repair work soon allowed the battle-cruiser to work her way up to 22 kt, Scharnhorst was now vulnerable to torpedo attacks by the British destroyers. Five minutes later, Bey sent his final radio message to the German naval command that his ship would fight on until the last shell had been fired.

At 18.50 Scharnhorst turned to starboard to engage the destroyers Savage and Saumarez, but this merely opened the way for Scorpion and Stord to deliver a torpedo attack, which scored one hit on the starboard side. As Scharnhorst continued to turn in an effort to avoid the torpedoes, Savage and Saumarez found themselves in good firing positions and scored three hits on the German battle-cruiser’s port side. Saumarez was hit several times by Scharnhorst's secondary armament of 150-mm (5.91-in) guns, and suffered 11 men killed and another 11 wounded.

The damage inflicted by the torpedo hits once again reduced Scharnhorst's speed to 10 kt, which allowed Duke of York to close the range rapidly. With Scharnhorst illuminated by star shells, Duke of York and Jamaica opened fire once more, at a range of only 10,400 yards (9510 m), and at 19.15 Belfast supplemented this fire from the north. The British vessels subjected the German ship to a deluge of fire, and the cruisers Jamaica and Belfast also launched their remaining torpedoes at their slowing target.

Scharnhorst's end came when the destroyers Matchless, Musketeer, Opportune and Virago fired a further 19 torpedoes at the German ship. Wracked with hits and unable to escape, Scharnhorst capsized and sank at 19.45 on 26 December, her propellers still turning. Of her total complement of 1,968 men, only 36 were pulled from the icy waters, 30 by Scorpion and six by Matchless. Neither Bey nor Hintze was among the survivors, though they had been seen in the water after their ship went down, and in fact no officers survived.

Fraser now ordered his ships to proceed to Murmansk.

Scharnhorst's loss served to confirm the vital importance of radar in modern naval warfare. While the German battle-cruiser should have been able to outgun all of her opponents except the battleship Duke of York, the early loss of her radar fire-control system combined with the heavy weather to leave her at a major fire-control disadvantage: as it was, Scharnhorst was straddled by 31 of the 52 salvoes fired by Duke of York with the benefit of radar fire control.

However, like other major German surface vessels, Scharnhorst had shown herself to be magnificently designed and superbly built, for her destruction had required the hits of at least 13 14-in (356-mm) shells from the battleship, of about 12 8- and 6-in (203- and 152-mm) shells from the cruisers, and of 11 hits from the 55 21-in (533-mm) torpedoes fired at her.

The Battle of the North Cape was the last battle between big gun capital ships in the war between the UK and Germany, and the British victory confirmed the massive strategic advantage the British possessed, at least in surface units.