'Polarbär' was the German 'triphibious' seaborne and airborne seizure of Kos in the Dodecanese islands group (3/4 October 1943).

With the implementation of the armistice between Italy and the Allies powers, implemented on the night of 8/9 September 1943, German forces in the Balkans and the Mediterranean moved to take over the Italian-held areas. At the same time, the Allies, under the instigation of British prime minister Winston Churchill, endeavoured to occupy the Dodecanese islands group in the Aegean Sea. Under Italian control since 1912, this island group was strategically sited in the south-eastern part of the Aegean Sea, and Churchill hoped to use it as a base against German positions in the Balkans, and as a means to pressure neutral Turkey into the war on the Allied side.

The most important of the islands, in the view of Churchill and others, was the island of Rhodes, but this fell to a swift attack by the German element of its garrison. Regardless of this fact, British forces landed on several islands, most notably Kos and Léros, and together with the Italian forces located there, there were hopes of eventually regaining Rhodes. Kos was occupied by the British on 14 September as a preliminary to 'Accolade' for the capture of Rhodes. On 13 September a force of 38 Consolidated Liberator heavy bombers, operating from bases in North Africa, had bombed the three airfields on Rhodes, thereby effectively grounding the German aircraft based there, while Special Boat Squadron personnel landed on Kos, occupying the port and the airfield near the village of Antimachia. On 14 September two Bristol Beaufighter heavy fighters and a number of Supermarine Spitfire fighters of No. 7 Squadron, South African Air Force, arrived on Kos’s airfield. On the night of the 14/15 September 120 men of the 11/Parachute were dropped by Douglas Dakota transports of No. 216 Squadron, RAF, and on landing were welcomed by the soldiers of the Italian garrison, who laid straw on the landing zone. From first light on 15 September, a standing patrol of two Spitfire fighters was maintained over Kos to provide cover for the transport aircraft and ships bringing in reinforcements and stores.

Among these were the first men of No. 2909 Squadron of the RAF Regiment, who were delivered from Palestine with nine 20-mm cannon for anti-aircraft defence, followed two days later by a second detachment, which brought up to strength one of the first of the regiment’s squadrons to be transported to the battlefield by air with all its weapons. On the ground, the Allied force now comprised the 1/Durham Light Infantry, 120 men of 11/Parachute’s A Company, a number of men from the Special Boat Service and RAF personnel under the command of Lieutenant Colonel L. R. F. Kenyon. The force totalled about 1,600 British (although only 1,115 were combatants in the form of 880 army and 235 RAF personnel) and about 3,500 Italian servicemen from the original garrison. Overall British command was exercised at great range by Lieutenant General Sir Desmond Anderson, commander of the III Corps in Iran and Iraq.

The German counter was 'Polarbär', planned by Generalfeldmarschall Maximilian Reichsfreiherr von Weichs, the Oberbefehlshaber 'Südost', who used one battalion of the 440^th Grenadierregiment (stationed in Lésbos and Khíos) and part of Generalleutnant Friedrich-Wilhelm Muller’s Crete-based 22^nd Division for the task of retaking the Aegean islands taken by the British during September.

The German counterattack began on 17 September with a heavy air attack. The Messerschmitt Bf 109 fighters and Junkers Ju 88 bombers initially met with varying success, for the RAF gunners on the ground and the Spitfire fighters in the air gave a good account of themselves, but bombing rendered Antimachia airfield temporarily unserviceable and damaged the Dakota transports, but the first detachments of the Durham Light Infantry were landed, although one Dakota came down in the sea and its occupants were rescued but interned in Turkey. German bombing and cannon fire attacks continued to harass the garrison over the next few days. The Germans flew 100 aircraft into the Aegean Sea area bringing their strength up to some 360 aircraft.

Moreover, while the German air cover improved, that of the Allies could rely on only a limited number of aircraft as a result of the decision made by General Dwight D. Eisenhower, the Mediterranean theatre commander, that British operations in the Aegean should in no way impinge on operations elsewhere in the Mediterranean theatre. Thus the air cover available for Kos was therefore wholly inadequate and totally undermined the practicality of the British position on Kos. Between 13 September and 3 October the Allied aircraft defending Kos suffered many losses in the air and also from bombardment of the airfield. No. 7 Squadron had been reduced to four serviceable aircraft by 26 September, the day on which No 74 Squadron of the RAF arrived on the island.

The defenders' position on Kos steadily deteriorated from poor to serious and finally to desperate, for the Italian anti-aircraft defence capability was negligible and their own resources meagre. To add to the defenders' problems, the area round the airfield they had to protect was too rocky to permit the creation of prepared defences, and there was no time to build blast walls before the German attack materialised. The air attacks were so severe that the British paratroopers suffered losses so severe that they had to be withdrawn on 25 September.

On 1 October a concentration of shipping was observed in the ports of Crete, and early on the following morning British aircraft sighted a convoy to the south-east of Mílos and steaming in a north-north-easterly direction. Urgent supplies were landed on Kos by five Dakota transport aircraft, and as these were being unloaded there arrived the news that a small German invasion fleet of 10 vessels was at sea. This German flotilla carried a task force comprising a Kampfgruppe of the 22^nd Division and special forces from the mainland, namely the 1^st Küstenjägerabteilung and 15^th Fallschirmkompanie of Generalmajor Alexander von Pfuhlstein’s Division 'Brandenburg'.

The German direct attack on Kos started at 04.30 on 3 October, and by 12.00 some 1,200 Germans, with light artillery and armoured cars, had come ashore and were in action. Attacks by Junker Ju 87 dive-bombers added to the difficulties of the Allied defence, and in the afternoon the German forces overran Antimachia. The main German convoy, which had been attacked from air, was estimated to have consisted of seven transports, seven landing craft, three destroyers and numerous caiques (fishing craft) and other small craft. The principal landings took place at Marmari and Tingachi (in the north central part of the island) and at Camare Bay (in the south-west) with subsidiary landings at Forbici and Capo Foco (on the north-eastern and south-eastern tips of the island). Paratroopers were dropped in company strength to the west and south of Antimachia. At about 13.30 a further small paratroop landing of men from the Division 'Brandenburg' was made in the centre of the island, and more troops arrived by sea.

For the British forces the situation was reported as confused, but by 18.00 it was further reported as critical. The 1/Durham Light Infantry, personnel of the Special Boat Service and a few remaining paratroopers of the 11/Parachute fought gallantly, but in the face of superior numbers and heavier equipment were forced to withdraw to positions covering the town and port of Kos and the airfield. That evening the Germans attacked the British positions in strength, steadily eroding the British position to a small area around the town of Kos. The German strength had been reinforced to an estimated 4,000 men by the evening of 3 October.

Organised resistance by the British and Italian forces had ended by 06.00 on 4 October, and some 1,388 British and 3,145 Italians were taken prisoner: some survivors of the British garrison had fallen back into the mountains above the south coast by the early hours of 4 October, and about 100 men were brought off by the Royal Navy.

The Germans shot the captured Italian commander of the island, Colonnello Felice Leggio, and 90 of his officers in accordance with Adolf Hitler’s order of 11 September that captured Italian officers who had taken up arms against Germany should be executed. A few British escaped to neighbouring islands and were rescued by the Special Boat Service operating at night. The Germans lost some 85 men, and had returned to their bases by 5 October, leaving only a small garrison on the island.

The capture of Kos had disastrous consequences for other British operations in the Dodecanese islands group. Deprived of air cover, the British not hold the other islands for any significant time, while the Germans pressed their advantage, capturing Léros a month later and completing their seizure of the Dodecanese islands group by the end of November.