The Battle of Leros (26 September and 16 November 1943) took place on the Greek island of Leros between the Allies and invading forces of Nazi Germany. Regarded as the central event of the Dodecanese campaign of the Second World War, the term is widely used as an alternative name for the campaign. After the Armistice of Cassibile the Italian garrison on the Greek island Leros was strengthened by British forces on 15 September 1943. The battle began with German air attacks, continued with the landings on 12 November and ended with the capitulation of the Allied forces four days later.

Background Armistice

After the Italian government had signed the armistice, the Italian garrisons on most of the Dodecanese either wanted to change sides and fight alongside the Allies or go home. The British tried to exploit this but the Germans were ready. As the Italian surrender became apparent, German forces, based largely in mainland Greece, were rushed to many of the major islands to gain control. The most important such force, the swiftly neutralised the garrison of Rhodes, denying its three airfields to the British.

Operation Accolade

After the Battle of Greece in April 1941 and the Battle of Crete (20 May – 1 June 1941) Greece and its many islands were occupied by German, Italian and Bulgarian forces. With the Armistice of Cassibile on 8 September 1943 the Greek islands, which were seen as strategically important by Winston Churchill, became a feasible objective for the first time since the loss of Crete.

The United States was sceptical about operations in the Aegean, which it saw as an unnecessary diversion from the Italian Campaign. This was confirmed at the Quebec Conference, where it was decided to divert all available shipping from the Eastern Mediterranean. The British persisted, albeit with a much smaller force. Air cover was limited with the US and British aircraft based in Cyprus and the Middle East, exacerbated by the withdrawal of the US units in late October to the Italian Campaign.

Kos and other islands By mid-September, the 234th Infantry Brigade (Major-General F. G. R. Brittorous) the former Malta garrison, detachments of the Special Boat Service (SBS) and Long Range Desert Group (LRDG) had secured the islands of Kos, Kalymnos, Samos, Leros, Symi and Astypalaia, supported by ships of the Royal Navy, Royal Hellenic Navy and two RAF Spitfire squadrons on Kos. The 22nd Infantry Division on Crete (Generalleutnant Friedrich-Wilhelm Müller) was ordered to take Kos and Leros on 23 September.

The British forces on Kos, under the command of Lieutenant Colonel L. R. F. Kenyon, numbered about 1,500 men, 680 of whom were from the 1st Battalion Durham Light Infantry, 120 men from 11th Parachute Battalion, a number of men from the SBS, the rest being mainly RAF personnel and Italians, primarily made up by the troops of the 10th Infantry Regiment "Regina" from the 50th Infantry Division "Regina". On 3 October, the Germans effected amphibious and airborne landings of Unternehmen Eisbär (Operation Polar Bear), reaching the outskirts of the capital later that day. The British withdrew under cover of night and surrendered the next day. The fall of Kos was a serious blow to the British, depriving them of air cover. The Germans captured 1,388 British and 3,145 Italian prisoners. On 4 October, German troops conducted the Massacre of Kos, in which Colonello Felice Leggio, and 101 of his officers were shot according to the 11 September order from Adolf Hitler to execute captured Italian officers.

Leros

The island of Leros is part of the Dodecanese archipelago in the south-eastern Aegean Sea. The island had been under Italian occupation since the Italo-Turkish War (29 September 1911 to 18 October 1912). During Italian rule, Leros, with its excellent deep-water port of Portolago (now Lakki), was developed into a fortified aeronautical and naval base, "the Corregidor of the Mediterranean", as Mussolini boasted. The island was base for some Italian naval units, in September 1943 the (4th Destroyer Flotilla) with the destroyer , III Flottiglia MAS (third MAS Flotilla) with two motor torpedo boats and six MAS, the XXXIX Minesweeper Flotilla with eleven boats and nine minor units, seven merchant ships, the s Azio and Legnano and three Italian-built Marinefährprahme.

Prelude Allied forces The Italian garrison of Leros numbered about 7,600 men, under the command of Captain Luigi Mascherpa. The vast majority of these men – 6,065, plus an additional 697 militarised personnel – belonged to the Royal Italian Navy, as Leros was mainly a naval base. The rest of the Italian force consisted of the I Fusilier Battalion of the 10th Infantry Regiment "Regina", the 8th Coastal Machine Gunners Company, and the 402nd Militia Machine Gunners Company from the Regio Esercito and 20 Regia Aeronautica reservists. Only about 1,000 were first-line troops; most belonged to technical and service units or to anti-aircraft detachments. The island's defences included thirteen coastal batteries (armed with nineteen 152 mm guns, five 102 mm guns, and twenty 76 mm guns), twelve anti-aircraft and dual purpose batteries (armed with fourteen 102 mm guns, six 90 mm guns, and twenty-eight 76 mm guns), and several machine guns (three 37 mm, fifteen 20 mm, and thirty-one 13.2 mm). Most of these, however, were poorly protected from air assault and, accordingly, would suffer badly from Luftwaffe attacks. The clauses of the armistice determined that all Italian naval vessels were to head for Malta or other Allied-controlled bases but Mascherpa persuaded the British command to allow his ships to remain in Leros, since they would be of more use there in the event of a German attack. The only aircraft available were seven outmoded CANT Z. 501 floatplanes

After the fall of Rhodes, some men from its garrison reached Leros and Mascherpa assumed command of all Italian naval forces in the Aegean and re-organised the Leros anti-aircraft defences. On 12 September, a delegation of British officers met Mascherpa to assess the island's defences and to inquire about what relations could be established between Italian and British troops; Mascherpa did not go too far in his replies, since the terms of the armistice were still rather vague. On the following day, more British officers arrived, including Major George Jellicoe and Colonel Turbull, who was disappointed by the state of the defences, particularly the anti-aircraft preparations. The Italians made the decision to fire on any German aircraft that flew over Leros. On 13 September, the Germans invited the Italians to surrender with "honourable conditions", which Mascherpa refused.

On 17 September the small Italian garrison of Alimia, after leaving their island on board two fishing boats, reached Leros with their weapons. The influx of soldiers from Rhodes and Alimia brought the total Italian troop strength to 8,320 and on the same day the first 400 British reinforcements arrived. On 20 September Captain Mascherpa, upon hearing that Major-General Frank G. R. Brittorous was coming to Leros, asked Supermarina, the high command of the for advancement to the rank of rear admiral, so that he would not be junior in rank to Brittorous. This was granted. On the same day, Brittorous reached Leros with 600 more men, food and equipment (carried by a steamer, two destroyers and smaller vessels). Brittorous published a proclamation in which he stated that he was in command and all Italian commands were subordinated to him; this immediately created friction with Mascherpa, who had been confirmed in command of all Italian forces on Leros, as well as the civilian population but was now subordinated to Brittorous. Both officers asked their commands for reinforcements, food and ammunitions but little arrived.

By October, the British forces on the island of Leros numbered ca. 3,000 men of the 2nd Bn The Royal Irish Fusiliers, (under Lt Col Maurice French), the 4th Bn The Buffs (The Royal East Kent Regiment) (Lt Col Douglas Iggulden), the 1st Bn The King's Own Royal Regiment (Lancaster), and a company of the 2nd Bn Queen's Own Royal West Kent Regiment, the whole force under Brigadier Robert Tilney, who assumed command on 5 November. Initially, the British had planned to secure the high ground of the island's interior, but Brig Tilney insisted on a forward defence on the coastline, which spread his forces too thinly.

The air force units detailed for this operation were not large. Apart from Dakota transport aircraft, there were two day and two night Beaufighter squadrons, a Wellington torpedo bomber squadron, three Baltimore and one Hudson General Reconnaissance squadrons and a detachment of Photographic Reconnaissance Spitfires. This force was based on the mainland of Africa and in Cyprus. Two heavy bomber squadrons, 178 Squadron and 462 Squadron RAAF of 240 Wing equipped with Liberators and Halifaxes and a Wing of the US IX Bomber Command took part at a later stage. The only real defensive force were two Spitfire squadrons 7 SAAF and 74 Squadron RAF. The number of aircraft was 144 fighters (single and twin-engined) and 116 heavy, medium and torpedo bombers; 115 were lost.

German forces The German forces assembling for (Operation Leopard) comprised III./Infanterie-Regiment 440, II./IR 16 and II./IR 65 of the 22nd Infantry Division, the parachutists of I./Fallschirmjäger (FJR) 2, and an amphibious commando company of the Brandenburg Division (1./Küstenjägerabteilung). The invasion force assembled in harbours in Kos and Kalymnos, with reserves and heavy equipment waiting to be airlifted around Athens. Two groups with Ju 87 D3 dive-bombers were available for close air support. I./Gruppe of Schlachtgeschwader 3 flew from their base in Megara and II./Gruppe from Argos and later Rhodos. II Gruppe of Kampfgeschwader 51 with Junkers Ju 88s were available for bombing.

On the night of 6/7 October, in the Astypalaia channel, the cruisers and and the destroyers and attacked a German troop convoy consisting of the auxiliary submarine chaser UJ 2111 (former Italian gunboat Tramaglio), the cargo ship Olympus and seven MFPs, sinking all but one MFP. These troops were meant as a reinforcement to the force for Operation Leopard and the destruction of the convoy caused the operation to be delayed.

+ raids Date Raids Sorties 26 September 2 25 27 September 1 30 28 September — —29 September 3 60 30 September 3 60 1 October — — 2 October — — 3 October 4 50 4 October 4 50 5 October 5 79 6 October 5 78 7 October 5 80 8 October 4 18 9 October 6 29 10 October 3 76 11 October 3 24 12 October 8 62 13 October — — 14 October 3 65 15 October 10 34 16 October 11 76 17 October 7 28 18 October 2 28 19 October 6 24 20 October 2 28 21 October — — 22 October 11 44 23 October 5 47 24 October 4 15 25 October 4 16 26 October 11 50 27 October 4 16 28 October — — 29 October — —30 October 1 5 31 October 1 6 Totals 141 1,203 Starting on 26 September, after days of dropping propaganda leaflets, the Luftwaffe began attacks on Leros, enjoying air superiority. On that day, Ju 88 bombers sank the Greek destroyer , the British destroyer and the Italian MAS 534 inside the harbour of Lakki. The submarine base, the barracks of the naval base, the workshops, and four of the five fuel depots (but not the one which actually contained fuel) were destroyed; seven German bombers were shot down.

Between 26 September and 11 November Leros was continuously bombed, an average of four raids and 41 bomber sorties per day between 26 and 30 September and eight raids of 37 bomber sorties daily between 7 October and 11 November. In addition to military objectives, the villages and towns, especially Leros and Lakki, suffered heavy damage. Hospitals had to be transferred to caves, and 10 per cent of coastal batteries, 30 per cent of anti-torpedo boat batteries and 20 per cent of anti-aircraft guns were destroyed.