East African Campaign On the outbreak of the
Second World War, Slim was given command of the
10th Indian Infantry Brigade of the
5th Indian Infantry Division and was sent to
Sudan. He took part in the
East African campaign to liberate
Ethiopia from the Italians. Slim was wounded again in
Eritrea. On 21 January 1941, he was hit when his vehicle was strafed by
Fiat CR.42 fighters during the advance on
Agordat.
Middle East Recovering from his wounds but still unfit for active service, Slim was temporarily employed on the General Staff at GHQ in Delhi. He was involved in the planning for potential operations in Iraq where trouble was expected. By early May 1941 Slim had been appointed Brigadier General Staff (chief staff officer) to
Edward Quinan the commander designate for operations in Iraq, arriving in
Basra on 7 May. Not long afterwards, Major-General
Fraser, commanding the
10th Indian Infantry Division, fell ill and was relieved of his command, and Slim was promoted to take his place on 15 May 1941 with the acting rank of
major-general. He led the Indian 10th Infantry Division as part of
Iraqforce during the
Anglo-Iraqi War, the
Syria–Lebanon campaign (where the division advanced up the river Euphrates to capture
Deir ez-Zor), and the
invasion of Persia. He was twice
mentioned in despatches during 1941.
Burma campaign . In March 1942, Slim was given command of
Burma Corps, also known as
BurCorps, consisting of the
17th Indian Infantry Division and
1st Burma Division. Slim was made acting
lieutenant general on 8 May 1942. The corps was under attack in Burma by the
Japanese and, heavily outclassed by the more mobile and flexible Japanese, was soon forced to withdraw to India. On 28 October 1942, Slim was appointed a Commander of the
Order of the British Empire (CBE). Slim then took over
XV Corps under the command of the Eastern Army. His command covered the coastal approaches from Burma to India, east of
Chittagong. He had a series of disputes with
Noel Irwin, commander of Eastern Army and, as a result, Irwin (although an army commander) took personal control of the initial advance by XV Corps into the
Arakan Peninsula. The operations ended in disaster, during which Slim was restored to command of XV Corps, albeit too late to salvage the situation. Generals Irwin and Slim blamed each other for the result, but in the end Irwin was removed from his command, and Slim was promoted to command the new
Fourteenth Army—formed from
IV Corps (United Kingdom) (Imphal),
XV Corps (Arakan) and XXXIII Corps (reserve) – later joined by XXXIV Corps. On 14 January 1943, Slim was appointed a Companion of the
Distinguished Service Order (DSO) for his actions in the Middle East during 1941. The American historians Alan Millet and Williamson Murray described Slim as: Slim quickly got on with the task of training his new army to take the fight to the enemy. His basic premise was that off-road mobility was paramount: much heavy equipment was exchanged for mule- or air-transported equipment, and motor transport was kept to a minimum and restricted to vehicles that could cope with some of the worst combat terrain on Earth. The new doctrine dictated that if the
Japanese had cut the
lines of communication, then they too were surrounded. All units were to form defensive 'boxes', to be resupplied by air and assisted by integrated close air support and armour. The boxes were designed as an effective response to the tactics of infiltration practised by the Japanese in the war. Slim also supported increased offensive patrolling and night training, to encourage his soldiers to lose both their fear of the jungle and their belief that Japanese soldiers were better jungle fighters. He also instructed them to hold their positions once outflanked. The
Chin Hills formed a natural defensive barrier into Burma, which Slim would have preferred to outflank by an amphibious operation by landing further down the coast of Burma, but demands of the war in Europe meant the necessary landing craft were not available, forcing Slim to devise plans for advancing into Burma overland through the Chin hills. At the same time, the
Japanese 15th Army, which formed the main striking force of the
Burma Area Army, had grown from four divisions at the beginning of 1943 to eight divisions by the end of 1943 as the Japanese made preparations for invading India, which increased the difficulties of an overland advance into Burma. By 1943, the
Burma Railway, which cost the lives of thousands of prisoners of war who built it, was finished; this allowed the Japanese to reinforce the Burma Area Army, and made invading India possible. As Slim went about training his men for the rigours of jungle warfare, he clashed with Brigadier
Orde Wingate, who took away some of Slim's best Gurkha, British and African units for his
Chindit raiding group. Slim argued against the loss of his better units to Wingate, and maintained that though Wingate had a successful career in Palestine and Ethiopia he would discover that the Japanese were a considerably tougher foe than the Palestinians and the Italians that Wingate had hitherto been fighting. However, Slim did approve of Wingate's plans for aid to the hill tribes of Burma. The various hill peoples of Burma such as the
Kachins,
Karens,
Chin,
Nagas and the
Shan collectively amounted to about 7 million of Burma's 17 million people, and unlike the
Bamars, who had welcomed the Japanese as liberators, had stayed loyal to the British when the Japanese invaded. The hill peoples of Burma had suffered under Japanese rule, and were more than willing to wage guerrilla warfare against them. Slim approved of the plans of the SOE and OSS to provide arms and training to the hill tribes as a way to tie down Japanese forces that would otherwise be deployed against him. At the start of 1944, Slim held the substantive rank of colonel with a war substantive rank of major-general and the acting, then upgraded to temporary, rank of lieutenant-general. In January 1944, when the
Second Arakan Offensive was met by a Japanese counter-offensive, the
Indian 7th Infantry Division was quickly surrounded along with parts of the
Indian 5th Infantry Division and the
81st (West Africa) Division. The 7th Indian Division's defence was based largely on the "
Admin Box" formed initially from drivers, cooks and suppliers. They were supplied by air, thus negating the importance of their lost supply lines. The Japanese forces were able to halt the offensive into Arakan but were unable to decisively defeat the allied forces or advance beyond the surrounded formations. In early 1944, the Japanese Prime Minister, General
Hideki Tojo, approved of plans for victory in Asia, calling for two operations,
Operation U-Go as the invasion of India was code-named and
Operation Ichi-Go which was intended to defeat China once and for all. The two operations in India and China were closely linked given that American supplies for China were flown over "
the Hump" of the Himalayas and the Japanese wanted to take the Indian province of
Assam in part to close the American air bases in India that sustained China at the same time that they were launching Operation Ichi-Go, the biggest Japanese offensive of all time, involving 2 million men. The Japanese knew that they lacked the logistics to invade India, and the plans for U-Go were based on the assumption that the British Fourteenth Army would just collapse, allowing the Japanese 15th Army to capture enough food to prevent its men from starving to death. Following the Japanese 15th Army into India was the
Indian National Army commanded by
Subhas Chandra Bose, an ardent nationalist. The Japanese believed that the mere presence of Bose in India would inspire the men of the Indian Army to mutiny and murder their British officers, and set off an anti-British revolution that would allow the Japanese 15th Army to take all of India. Slim was appointed a
Companion of the Order of the Bath (CB) in the
1944 New Year Honours. and, on 28 September 1944, he was appointed a
Knight Commander of the Order of the Bath (KCB). In December 1944, during a ceremony at Imphal in front of the Scottish,
Gurkha and
Punjabi regiments, Slim and three of his corps commanders (
Christison,
Scoones and
Stopford) were knighted by the viceroy
Lord Wavell and invested with honours. Slim was presented with his insignia as KCB, and the others with their
KBEs. Slim was also mentioned in despatches. By the end of 1944, the majority of the men serving in the British Fourteenth Army were in fact not British as of the 12 divisions that made up the British Fourteenth Army, 2 were British, 7 were Indian and 3 came from Britain's African colonies. In addition, there were six Chinese divisions, two regiments from the U.S. Army and various tribal militias made up of Shan, Chin, Naga, Kachin and Karen peoples raised by the OSS and the SOE fighting on the Allied side in Burma, requiring Slim to play the role of the diplomat as much as a general to hold these disparate forces made up of so many different peoples together. , near Imphal, December 1944. In 1945, Slim launched an offensive into Burma, with
supply lines stretching almost to the breaking point across hundreds of miles of trackless jungle. Slim employed Billy Williams and his corps of elephants, led by Bandoola, to build bridges and rescue refugees. He faced the same problems that the Japanese had faced in their failed 1944 offensive in the opposite direction. He made the supply of his armies the central issue in the plan of the campaign. The
Chindwin River was spanned with the longest
Bailey bridge in the world at the time. To distract the Japanese from his campaign in central and southern Burma, Slim ordered the Chinese in northern Burma to begin an offensive, which for a time led the Japanese to the erroneous conclusion that the main goal of the Allies was to open the
Burma Road to China. Slim began his advance by sending two corps towards
Mandalay and another corps along the coast towards
Rangoon, but changed his plans when he learned from intelligence that the Japanese were planning on defending Mandalay from the eastern banks of the
Irrawaddy River. Slim had one corps cross the Irrawaddy south of Mandalay at
Meiktila while another corps staged a feint attack on Mandalay from the north to distract the Japanese from the main blow coming up from the south. The swift flowing Irrawaddy is a wider river than the
Rhine, making it into a natural defensive barrier that the Japanese believed could halt the British advance. However, much of the countryside around the Irrawaddy consists of plains that favoured the offensive, and in his operations in the Irrawaddy river valley, Slim used
combined arms offensives with artillery and tanks working closely with the infantry to bring down overwhelming firepower when the Japanese tried to block the British Fourteenth Army's advance. In March 1945, after crossing the Irrawaddy, the town of Meiktila was taken, followed by Burma's second city, Mandalay. (AOC 221 Group South East Asia Air Forces, centre) and Major General
Henry Chambers (GOC 26th Indian Division, right) at
Government House, Rangoon, 8 May 1945. The Japanese garrison in Mandalay chose not to surrender, using the forts built by the British and the maze of pagodas in downtown Mandalay to fight to the death in
an urban battle that destroyed much of the city, which finally fell to the British Fourteenth Army on 20 March 1945. Slim's plan was a masterpiece of
operational art, and the capture of Meiktila left most of Japan's troops stranded in Burma without supplies. The Allies had reached the open plains of central Burma, sallying out and breaking Japanese attacking forces in isolation, maintaining the initiative at all times, backed up by air-land cooperation, including resupply by air and close air support, performed by both RAF and USAAF units. Slim followed up this victory by ordering his coastal corps to seize the mouth of the Irrawaddy where it flowed into the
Bay of Bengal. In combination with these attacks,
Force 136 helped initiate a countrywide uprising of the
Bamar people against the Japanese. In addition to fighting the allied advance south, the Japanese were faced with heavy attacks from behind their own lines. As he advanced into Burma, Slim discovered gruesome evidence of the nature of Japanese rule in Burma, finding in village after village, Burmese peasants who had been tied to trees and bayoneted to death as the Japanese preferred bayonet practice with people rather than sandbags as normally is the case. Toward the end of the campaign, the army raced south to capture
Rangoon before the start of the monsoon. It was considered necessary to capture the port because of the length of the supply lines overland from India and the impossibility of supply by air or land during the monsoon. Rangoon was eventually taken by a combined attack from the land (Slim's army), the air (parachute operations south of the city) and
a seaborne invasion. Also assisting in the capture of Rangoon was the
Anti-Fascist People's Freedom League led by
Thakin Soe, with
Aung San (the future Prime Minister of Burma and father of
Aung San Suu Kyi) as one of its military commanders. and Vice-Admiral
Sir Arthur John Power outside Singapore's municipal building, following Japan's ceremonial surrender of the city, 12 September 1945. As the Burma campaign came to an end, Slim was informed in May by
Oliver Leese, the commander of
Allied Land Forces South-East Asia (ALFSEA) that he would not be commanding Fourteenth Army in the forthcoming invasion planned for
Malaya but would take command of the new
Twelfth Army being formed to mop up in Burma. Slim refused the appointment, saying he would prefer to retire. As the news spread, Fourteenth Army fell into turmoil and
Alan Brooke, the
Chief of the Imperial General Staff, furious at not having been consulted by Leese, and
Claude Auchinleck, the C-in-C India who was at the time in London, brought pressure to bear. The Supreme Allied Commander of the Southeast Asia Theatre,
Louis Mountbatten was obliged to order Leese to undo the damage. On 1 July 1945, Slim was promoted to
general and was informed that he was to succeed Leese as C-in-C ALFSEA. However, by the time he took up the post, having taken some leave, the war was at an end.
Relations with troops . Slim had an excellent relationship with his troops – the "
Forgotten Army", as they called themselves. Slim had a close rapport with the officers and soldiers under his command, and always trusted his officers to make the correct decisions without referring to him. As Slim later wrote: "I was, like other generals before me, to be saved ... by the resourcefulness and the stubborn valour of my troops." Murray and Millet wrote that Slim's willingness to delegate authority down to his officers on the spot played a key role in sustaining his advance into Burma as officers did not have to wait for a decision from him. In the aftermath of Kohima and Imphal, Slim inspected the battlefields, seeing the bodies of wounded Japanese soldiers who had been killed by their comrades as under the code of
Bushido, which graphically showed to Slim how far the Japanese were willing to take
Bushido. Slim realized that Japanese logistics had broken down, but that Japanese soldiers were still prepared to fight to the death. That led him to the conclusion that it was better to outflank and bypass the Japanese positions as much as possible, leaving the Japanese to starve to death rather than engaging them in combat. The Japanese Burma Area Army had about 100,000 men while the British Fourteenth Army had only about 21,000 men. But Slim believed that with superior mobility backed by proper supply line, he could defeat the Japanese, whose logistics were poor. The superior Japanese numbers together with the fact that the Indian Army was an all-volunteer force, with only so many Indians willing to volunteer and the fact that sending fresh British troops to Burma was not a priority in London, made it imperative for Slim to save the lives of his men as much as possible. Slim was painfully aware that it would be difficult to replace whatever losses his men took, and had no intention of having his army being ground down by fighting the Japanese in every single place that they were. Slim was determined to save the lives of his men as much as possible, while Japanese officers, motivated by
Bushido, were ready to have all of their men die for the Emperor. Slim estimated that for every man killed under his command, the Japanese lost a hundred men. Slim noted 70% malaria rates among his troops, largely because they refused to take foul-tasting
mepacrine. Slim did not blame his medics for this problem, but placed the responsibility on his officers. He wrote: "Good doctors are no use without good discipline. More than half the battle against disease is fought not by the doctors, but by the regimental officers." After Slim dismissed some officers for high unit malaria rates, the others realised he was serious and malaria treatment was enforced, dropping the rate to less than five per cent. The combat effectiveness of his army was thus greatly enhanced. This physical and mental turnaround in the army under him was a contributing factor to the eventual defeat of the Japanese in Burma. Novelist
George MacDonald Fraser, then a nineteen-year-old lance corporal, recalled: and: ==Post-war career==