The Battle of Madagascar (5 May – 6 November 1942) was an Allied campaign to capture the Vichy French−controlled island Madagascar during World War II. The seizure of the island by the British was to deny Madagascar's ports to the Imperial Japanese Navy and to prevent the loss or impairment of the Allied shipping routes to India, Australia and Southeast Asia. It began with Operation Ironclad, the seizure of the port of Diego-Suarez (now Antsiranana) near the northern tip of the island, on 5 May 1942.
A campaign to secure the rest of the island, Operations Stream, Line and Jane, was opened on 10 September. The Allies broke into the interior, linking up with forces on the coast and secured the island by the end of October. Fighting ceased and an armistice was granted on 6 November. This was the first big operation by the Allies combining sea, land and air forces. The island was placed under Free French control.
Background
Geopolitical
Diego-Suarez is a large bay, with a fine harbour, near the northern tip of the island of Madagascar. It has an opening to the east through a narrow channel called Oronjia Pass. The naval base of Diego-Suarez lies on a peninsula between two of the four small bays enclosed within Diego-Suarez Bay. The bay cuts deeply into the northern tip of Madagascar's Cape Amber, almost severing it from the rest of the island. In the 1880s, the bay was coveted by France, which claimed it as a coaling station for steamships travelling to French possessions farther east. The colonization was formalized after the first Franco-Hova War when Queen Ranavalona III signed a treaty on 17 December 1885 giving France a protectorate over the bay and surrounding territory; as well as the islands of Nosy Be and St. Marie de Madagascar. The colony's administration was subsumed into that of French Madagascar in 1897.
In 1941, Diego-Suarez town, the bay and the channel were well protected by naval shore batteries.
Vichy
Following the Japanese conquest of Southeast Asia east of Burma by the end of February 1942, submarines of the Imperial Japanese Navy moved freely throughout the north and eastern expanses of the Indian Ocean. In March, Japanese aircraft carriers raided merchant ships in the Bay of Bengal, and attacked bases in Colombo and Trincomalee in Ceylon (now Sri Lanka). This raid drove the British Eastern Fleet out of the area and they were forced to relocate to a new base at Kilindini Harbour, Mombasa, Kenya.
The move made the British fleet more vulnerable to attack. The possibility of Japanese naval forces using forward bases in Madagascar had to be addressed. The potential use of these facilities particularly threatened Allied merchant shipping, the supply route to the British Eighth Army and also the Eastern Fleet.
Japanese Kaidai-type submarines had the longest range of any Axis submarines at the time – more than 10,000 mi (16,000 km) in some cases. If the Imperial Japanese Navy's submarines could use bases on Madagascar, Allied lines of communication would be affected across a region stretching from the Pacific and Australia, to the Middle East and as far as the South Atlantic.
On 17 December 1941, Vice Admiral Fricke, Chief of Staff of Germany's Maritime Warfare Command (Seekriegsleitung), met Vice Admiral Naokuni Nomura, the Japanese naval attaché, in Berlin to discuss the delimitation of respective operational areas between the German Kriegsmarine and Imperial Japanese Navy forces. At another meeting on 27 March 1942, Fricke stressed the importance of the Indian Ocean to the Axis powers and expressed the desire that the Japanese begin operations against the northern Indian Ocean sea routes. Fricke further emphasized that Ceylon, the Seychelles, and Madagascar should have a higher priority for the Axis navies than operations against Australia. By 8 April, the Japanese announced to Fricke that they intended to commit four or five submarines and two auxiliary cruisers for operations in the western Indian Ocean between Aden and the Cape of Good Hope, but they refused to disclose their plans for operations against Madagascar and Ceylon, only reiterating their commitment to operations in the area.
Allies
The Allies had heard the rumours of Japanese plans for the Indian Ocean and on 27 November 1941, the British Chiefs of Staff discussed the possibility that the Vichy government might cede the whole of Madagascar to Japan, or alternatively permit the Japanese Navy to establish bases on the island. British naval advisors urged the occupation of the island as a precautionary measure. On 16 December, General Charles de Gaulle, leader of the Free French in London, sent a letter to the British Prime Minister, Winston Churchill, in which he also urged a Free French operation against Madagascar. Churchill recognised the risk of a Japanese-controlled Madagascar to Indian Ocean shipping, particularly to the important sea route to India and Ceylon, and considered the port of Diego-Suarez as the strategic key to Japanese influence in the Indian Ocean. However, he also made it clear to planners that he did not feel Britain had the resources to mount such an operation and, following experience in the Battle of Dakar in September 1940, did not want a joint operation launched by British and Free French forces to secure the island.
By 12 March 1942, Churchill had been convinced of the importance of such an operation and the decision was reached that the planning of the invasion of Madagascar would begin in earnest. It was agreed that the Free French would be explicitly excluded from the operation. As a preliminary battle outline, Churchill gave the following guidelines to the planners for Operation Bonus:
- Force H, the ships guarding the Western Mediterranean, should move south from Gibraltar and should be replaced by an American Task Force
- The 4,000 men and ships proposed by Lord Mountbatten for the operation should be retained as the nucleus around which the plan should be built
- The operation should commence around 30 April 1942
- In the event of success, the commandos recommended by Mountbatten should be replaced by garrison troops as soon as possible
On 14 March, Force 121 was constituted under the command of Major-General Robert Sturges of the Royal Marines with Rear-Admiral Edward Syfret being placed in command of naval Force H and the supporting sea force.
Allied preparations
Force 121 left the Clyde in Scotland on 23 March and joined with Syfret's ships at Freetown in Sierra Leone, proceeding from there in two convoys to their assembly point at Durban on the South African east coast. Here they were joined by the 13th Brigade Group of the 5th Division – General Sturges' force consisting of three infantry brigades, while Syfret's squadron consisted of the flag battleship HMS Ramillies, aircraft carriers HMS Illustrious and HMS Indomitable, cruisers HMS Hermione and HMS Devonshire, eleven destroyers, six minesweepers, six corvettes and auxiliaries. It was a formidable force to bring against the 8,000 troops (mostly conscripted Malagasy) at Diego-Suarez, but the chiefs of staff were adamant that the operation was to succeed, preferably without any fighting.
This was to be the first British amphibious assault since the disastrous landings in the Dardanelles twenty-seven years before.
During the assembly in Durban, Field-Marshal Jan Smuts pointed out that the mere seizure of Diego-Suarez would be no guarantee against continuing Japanese aggression and urged that the ports of Majunga and Tamatave be occupied as well. This was evaluated by the chiefs of staff, but it was decided to retain Diego-Suarez as the only objective due to the lack of manpower. Churchill remarked that the only way to permanently secure Madagascar was by means of a strong fleet and adequate air support operating from Ceylon and sent General Archibald Wavell (India Command) a note stating that as soon as the initial objectives had been met, all responsibility for safeguarding Madagascar would be passed on to Wavell. He added that when the commandos were withdrawn, garrison duties would be performed by two African brigades and one brigade from the Belgian Congo or west coast of Africa.
In March and April, the South African Air Force (SAAF) had conducted reconnaissance flights over Diego-Suarez and No. 32, 36 and 37 Coastal Flights were withdrawn from maritime patrol operations and sent to Lindi on the Indian Ocean coast of Tanganyika, with an additional eleven Bristol Beauforts and six Martin Marylands to provide close air support during the planned operations.
Campaign
Allied commanders decided to launch an amphibious assault on Madagascar, Operation Ironclad, executed by Force 121. It included Allied naval, land and air forces and was commanded by Major-General Robert Sturges of the Royal Marines. The British Army landing force included the 29th Independent Infantry Brigade Group, No 5 (Army) Commando, and two brigades of the 5th Infantry Division, the latter en route to India with the remainder of the division. The Allied naval contingent consisted of over 50 vessels, drawn from Force H, the Home Fleet and the British Eastern Fleet, commanded by Syfret. The fleet included the aircraft carrier HMS Illustrious, her sister ship Indomitable and the ageing battleship HMS Ramillies to cover the landings.
Landings (Operation Ironclad)
Following numerous reconnaissance missions by the South African Air Force, the first wave of the British 29th Infantry Brigade and No. 5 Commando landed in Landing Craft Assault on 5 May, with follow-up waves by two brigades of the 5th Infantry Division and Royal Marines. All were carried ashore by landing craft to Courrier Bay and Ambararata Bay, just west of the major port of Diego-Suarez, at the northern tip of Madagascar. A diversionary attack was staged to the east. Air cover was provided mainly by Fairey Albacore and Fairey Swordfish torpedo bombers which attacked Vichy shipping and the airfield at Arrachart. They were supported by Grumman Martlet fighters from the Fleet Air Arm. A small number of SAAF planes assisted. The Swordfish sank the armed merchant cruiser Bougainville and then the submarine Bévéziers; one Swordfish was shot down by anti-aircraft fire and its crew taken prisoner. The aircraft shot down had been dropping leaflets in French that encouraged the Vichy troops to surrender.
The defending Vichy forces, led by Governor General Armand Léon Annet, included about 8,000 troops, of whom about 6,000 were Malagasy tirailleurs (colonial infantry). A large proportion of the rest were Senegalese. Between 1,500 and 3,000 Vichy troops were concentrated around Diego-Suarez. Naval and air defences were relatively light or obsolete with eight coastal batteries, two armed merchant cruisers, two sloops, five submarines, 17 M.S. 406 fighters and ten Potez 63 bombers.
The beach landings met with virtually no resistance, and these troops seized Vichy coastal batteries and barracks. The Courier Bay force, the British 17th Infantry Brigade, after toiling through mangrove swamp and thick bush, took the town of Diego-Suarez and captured a hundred prisoners. The Ambararata Bay force, the 29th Independent Brigade, headed towards the French naval base of Antisarane. With assistance from six Valentines of 'B' Special Service Squadron and six Tetrarch light tanks of 'C' Special Service Squadron, they advanced 21 mi (34 km), overcoming light resistance with bayonet charges. Antisarane was elaborately defended with trenches, two redoubts, and pillboxes, and flanked on both sides by impenetrable swamps. Arrachart airfield was attacked, and five of the Morane fighters were destroyed and another two damaged, while two Potez-63s were also damaged. This attack eliminated a quarter of Vichy air strength on the island. Two Morane fighters did briefly appear and strafe beaches at Courier Bay, but two more Vichy aircraft were lost on the first day.