This time, his vehicle was not a motor car, not an aeroplane, and not the Frontier Mail. Instead, it was a submarine, the Unterseeboot 180 (or U-180), skulking low in the icy water at the mouth of a Baltic fjord by Laboe, at the northern tip of Germany.

The U-180 was an almost unique model, a long-range sub with its forward torpedo tubes removed to create a hold for extra cargo. On this mission, it was loaded with diplomatic mail for the German embassy in Tokyo, blueprints of jet engines and other technical material for the Japanese military. On 9 February 1943, its final freight arrived in a motorboat from the beach: two Indian passengers.

The U-180 was headed west, to cross the North Sea and pass beneath the heavily mined British waters. Inside the leviathan, where they would spend more than two months, it was dark, and the air reeked of diesel. “The fumes permeated everything," Hasan wrote in dismay, “The bread we ate looked as if it was soaked in diesel oil, the blankets seemed drenched with it." The area reserved for the Indians was only a recess in a passageway that served as an officers’ mess, or, when required, the medic’s surgery area. “Our corner was so small," Hasan recorded, “that if you stood erect, you got in the way of somebody or the other."

Despite the airless confinement, it was an exhilarating moment for Bose. He was meant to be writing up a new instalment of his memoir, The Indian Struggle, but what occupied his mind was the future, and a new scenario with vast potential in the East. Perhaps this was when he first tested those two words, Dilli chalo, which would soon be never far from his lips. That motto expressed the great purpose of Bose in his final years: to free India of the Raj. But it also reflected another attribute of his life: that he was a hardy and intrepid traveller, always ready to chalo (go) to somewhere far away and hard to reach, in the hope of one day arriving in free Delhi.

In the early 1940s, the world was at war, and India was convulsed by the August kranti, the freedom movement’s harsh climax. For most leaders of the Indian National Congress, it was a dreary and immobile time: They spent it stuck in jail. But for Bose it was a period of dramatic voyages, often made in secret, in danger, or incognito. It had begun in 1941 with a journey disguised as a Pathan in a car, when he broke out of house arrest in Calcutta, as Kolkata was then called. It would end too with a journey: aboard a plane leaving Formosa (now Taiwan), which crashed in 1945.

In between, there was the pivotal journey that might have been the most remarkable of all, across half the span of the world, at times beneath the waves. Details of this journey had been sparse, glossed over even in biographies written about Bose, until 2010, when they were excavated from German military sources by an unlikely duo of Danish researchers, Martin Bamber and Aad Neeven, and put in their self-published volume, For Free India.

Prior to boarding the U-180, Bose had spent two increasingly frustrating years in Fascist Europe. Having made his antic escape from Calcutta, through Peshawar and the Khyber, through Kabul, Samarkand and Moscow, Bose reached Berlin in the April of 1941. There, he set about winning access to men further and further up the Nazi hierarchy, and manoeuvring for Germany’s formal recognition of free India and its government-in-exile.

Finally, he met Hitler at the Wolf’s Lair, the chancellor’s military headquarters in East Prussia. Bose was disappointed, as he had been all along: Hitler aimed to destroy the British empire, but he never meant to discredit its logic, especially on the matter of enslaving other nations. He had written, right there in Mein Kampf, that he, “as a German, would far rather see India under British domination than under that of any other nation".

The Germans were far more enthused by Bose’s other idea, which had first come up in his meeting with the foreign minister, Joachim von Ribbentrop. The idea was to raise a liberation army from the Indian prisoners of war (POWs) then in German captivity. This was swiftly authorized, and by the time Bose left Germany, a Legion Freies Indien was serving as a regiment of the Wehrmacht. For Bose’s purposes, though, it was already too late. By now, the Axis powers had waded into the Soviet Union, and the heroic Red Army had dragged down any hope that German Panzers might clear a path to the Indian frontier—or, for Bose, to Delhi.

On 3 March, the U-180 refuelled at a U-tanker in the mid-Atlantic, then continued south. While Hasan joked and groused with the crew, Bose kept to himself, writing and missing his German wife and daughter, whom he would not see again.

“He worked more than anyone I knew,’ Hasan wrote in his own memoir, The Men from Imphal. “He hardly retired for the night before two o’clock in the morning and there is no instance to my knowledge when at sunrise he was found in bed." Yet the obsession, Hasan said, was a blessed escape from their airless confinement. “He had so many plans for the struggle in East Asia and they had all to be worked out and, as was his habit, each one in detail."

There were lighter moments, too, like the one Musenberg caught in a photo: a sailor dressed as Lord Neptune, in a paper crown and beard, “baptizing" a shirtless Bose on the occasion of his first equatorial crossing. The crew had a nickname for him now, a high compliment; they called him the “Indian Adolf".

The U-180 rounded the Cape of Good Hope. On 18 April, Musenberg caught the scent of a British tanker, the MV Corbis, and allowed himself a small diversion to torpedo it (it sank, with only 10 survivors). Warmed up, Musenberg ordered the pursuit of another enemy merchantman.

In their cubby, Bose was drafting a speech to Indian women, whom he believed could join the armed campaign— the women who would eventually form the Rani Jhansi regiment of the INA. At the bridge, Musenberg coordinated his attack. Suddenly: engine trouble. Just as Musenberg was preparing to give the order to fire torpedos, the U-180 was forced to the surface. The desperate British freighter turned, and Hasan recalls, “bore down on us with full speed to ram us".

Over the sub’s internal communication system, Bose and Hasan could hear everything.

“Dive!" the Captain shouted. “Dive! Dive!’"

Hasan saw “death reflected in some of the faces" visible around him, and he wondered later what he looked like himself in that instant. Bose’s reaction was more sanguine.

“Hasan", he remonstrated, “I have repeated a point twice and you are not noting it down".

“With violently beating heart and shaking fingers", Hasan went back to his dictation.

With a jolt, the U-180 keeled to one side and dropped down into the water. It was a while before Hasan was reassured that they had executed a dive, and the freighter had “only scratched the railings of our bridge." Musenberg quietly returned the U-180 to its main task.

On 20 April, it was sunset up above, and down in the deep, the U-180’s hydrophone operator picked up the sound of a diesel engine. They had reached their target location, south-west of Madagascar, and Musenberg felt confident that this was their appointed rendezvous. Cautious, he brought the U-180 to surface where it would be hard to spot in the shadows of the disappearing sun. The other vessel could not be seen.

Only at dawn did the Germans sight the other submarine, and exchange flag signals with its crew. Musenberg was nervous about his fuel levels, and keen to complete his mission, but the ocean was rough and heaving. For most of that day, and the two days that followed, the vessels cruised north together, waiting for the weather to calm, watching the skies for enemy aircraft. On sundown of the third day, a German officer and a signalman took the plunge into the water, and swam the swells to the Japanese submarine, dragging a thick hemp rope out with them. A while later, they returned to the U-180, aboard a rubber dinghy tethered to the rope. They would now attempt the transfer.

First across was the cargo: the diplomatic mail and technical papers exchanged for more documents, stores of quinine and gold ingots. Bose and Hasan packed their things and wrote a farewell note in the submarine unit’s diary, thanking the crew for “spoiling" them, as far as that had been possible. On 27 April, they strapped on life jackets, dropped into a raft and clung to its webbing as it pitched out over the Indian Ocean.

The crossing was short, and only took minutes. But it was a nautical feat without precedent in the war—the only sub-to-sub transfer of civilians in hostile waters—and a microscopic symbol for a greater, global shift along the same axis. A week before Bose’s departure, in February, the Wehrmacht’s 6th Army was smashed at the Stalingrad port, the most fateful turn in the war in Europe. By April, when Bose approached Sumatra, the Japanese army would be dusting itself off after thrashing British and Indian troops in the Arakan peninsula, priming their reputation as the masters of jungle warfare.

In those months, India, pinned between the two theatres, would start to swivel from west to east—to face, at last, the enemy at its own back gate, instead of the one that threatened the British Isles. And the eventual arrival of Bose and his nationalist army on the Indian border would turn that campaign into a moral furnace from which emerged a new, and irreversibly changed, Indian National Army.

For now, however, Bose was still being pulled up on to the deck of the Japanese scouting sub, the I-29. Its commander was Teraoka Masao, an officer celebrated for his part in the destruction of Britain’s flagships, the HMS Repulse and the HMS Prince Of Wales, back in 1941. Aboard the I-29, Teraoka gave his own cabin over to the Indian guests; it all felt, Hasan wrote, “something akin to a homecoming". Before they sailed, the Japanese crew had gone out shopping for Indian spices in Penang, Malaysia. Now they served Bose and Hasan a hot curry, to celebrate their crossing, and the birthday of the emperor in whose realm they had just arrived.

The U-180 could now turn back to Bordeaux, France, and Bose could proceed on his arc across the world, riding east to Sabang on the tip of Sumatra, Indonesia. He had had many names so far—Mr Ziauddin, Orlando Mazzotta, “Indian Adolf"—and now, aboard the I-29, he was “Mr Matsuda". From Sabang, Bose would continue on to Singapore, and then Tokyo and he would take command of the INA, beginning the most admired chapter of his personal epic. He stayed in motion, touring Japanese-occupied Asia to raise men and funds from euphoric crowds of migrant Indians. He visited the Andamans, late in 1943, to accept the island chain as the first official territory of Azad Hind.

His motto was always Dilli chalo, and though he never did make it, his aim never wavered. In August of 1945, after Japan’s unconditional surrender, Bose spoke a few words to disband the INA—words that still came from the idiom of a traveller. “The roads to Delhi are many," he said to them. “And Delhi still remains our goal."

Raghu Karnad is a contributing editor at, and the author of Farthest Field: An Indian Story Of The Second World War.