There's going to be some bleed over into the post-war era here, but I wanted to go ahead and get this out there!
A New India
Sree Chithira Thirunal, Maharaja of Travancore and First Emperor of the Empire of Hindustan and Moslemstan
The British Raj during the war had a complicated relationship with London. Many Hindus joined Gandhi's Aryan Empire League as a way to get ahead, but were not fanatical Empire patriots. However, they did have a vested interest in seeing the Empire succeed in the war, at least initially. However, as Britain faltered across the globe, many Hindus began expressing doubts, to say nothing of the Buddhists, Sikhs, Jainists, and especially the Muslims. This was compounded by the sheer quantity of men and material Britain expected from the Raj, and ongoing resentment to White dominance in the subcontinent. Despite this, the AEL and the colonists managed to keep the Raj going for four years under total war conditions, which was rather remarkable given the circumstances. However, the system could only take so much.
Soviet interference would doom the Raj to collapse. Afghan warlords supplied Muslims in the north of the Raj with the tools to wage a genuine insurrection against their overlords. When the AEL lashed out at the Muslims in Karachi on October 11th, 1942, the last day of Ramadan, the locals responded by hanging over 200 AEL members and colonial administrators. Similar actions took place across Muslim majority regions in the Raj. In turn, Hindus began harassing Muslims in Hindu-majority areas, even as AEL membership cratered. British forces in Persia rushed home to try and stop the bleeding, as the subcontinent threatened to spiral into a nightmare of religious warfare and anti-British rebellion. Throughout October and November the sepoys of Britannia as well as troops from the Dominions held the line against the spiraling situation. Then on December 2nd, 1942, a Muslim extremist shot AEL founder Mahatma Gandhi, killing him instantly. What followed was an explosion from AEL diehards. In New Delhi, 10,000 AEL extremists with rifles, swords, and clubs hunted Muslims for sport on December 4th, sparking revenge killings. Prime Minister Mosley made an emergency address on the BBC urging the aggrieved AEL members to "demonstrate calm, like the civilized men you are." This turned out to be a useless gesture. If anything, it made the AEL fear that London was going to abandon them to be killed by Muslims.
As the situation spiraled out of control, local military leaders became increasingly desperate. While before the military had tried to at least treat AEL fanatics with a mild hand, this was proving untenable. However, among the native-born troops who formed the majority of the British forces there, the increasing brutality with which they were being ordered to fight their countrymen was wearing them down. On New Year's Eve, 1942, a British general and his two colonels ordered a brigade of Indian troops to open fire on a rioting crowd in Bombay. Instead, the troops hanged their white officers. The Second Sepoy Revolt had begun. Across India, native troops turned on their overseers. Britain rushed every loyal white troop they could to the colony, but had trouble maintaining control of anything more than ports, railroads, and some key resources. Mosley ordered the "temporary" evacuation of all white civilians on February 10th, 1943. Once they had been safely loaded onto boats, Mosley ordered the RAF to drop poison gas on Indian villages and cities, starting on the 22nd. This killed thousands, but rebelling sepoys seized anti-aircraft guns and gave hell to an increasingly worn down RAF. So, the Mosley government changed tactics. On March 1st, the Royal Navy announced a blockade around the Raj. This compounded growing anarchy and food shortages, the latter exacerbated by poor harvests in '42 and British confiscations. Even as Dominion troops withdrew from the Raj, Mosley felt he could starve the subcontinent into submission. The Raj didn't starve completely, but did collapse into shortage and religiously induced anarchy. This was obviously terrible for your average Indian, regardless of religion or caste. However, one class benefitted.
The maharajahs of India, accustomed to privilege, had been sidelined by the Mosley government as less useful than the AEL. Given the sheer size of the League, the old princes begrudgingly took their licks. However, with the collapse of British rule on the subcontinent, the Princely States had actually been relatively untouched thanks to their neglect at the hands of the British. Furthermore, the wealth of the maharajahs meant they could buy guns, ammo, food, and other supplies from smugglers or corrupt British officials. There was a period of warring between these Princely States, which actually outlasted the Second World War. Even after the British blockade had passed with the conclusion of the war in late 1944, the massive disruption to life in India meant that the situation barely improved. Even more alarmingly, Communist troops were amassing on the border with Persia. It seemed likely that the Communists would overrun at least part of India, maybe all of it. However, it was not to be.
Maharajah Sree Chithira Thiruanl of the Kingdom of Travancore was, at the age of 33, fairly young for a ruler. He was also perceptive: there was no point in beating one's neighbors today if tomorrow Stalin was making you speak Russian. Instead, he aligned with the powers of Europe. On April 11th, 1945, he made a dramatic appearance in Tripartite Ceylon via submarine blockade runner. He spent several days communicating with Berlin and Vienna, conveying just how severe the situation had gotten. The subcontinent had become a humanitarian disaster area, and the Communists very well could have seized the country. The implications on the balance of global power were apparent. Using this pretext, the Young Maharajah struck a remarkably bold deal. He essentially secured European, and later even American aid and personnel, for nothing. After all, if the Communists thought that another foreign power was going to seize India, they would invade. Hardly good form to start WWIII barely after WWII had ended, right? Reluctantly conceding the point, some 5,000 German and European troops poured in, and promptly began handing out food. Germany announced an ongoing relief effort which much of the world signed onto, thwarting a Communist attempt to attack. Meanwhile, the Germans and Tripartite donated huge amounts of surplus military gear. In control of a vast arsenal and source of food, Sree forced compliance onto the subcontinent. He had the guns and the food, so he was in charge. On November 17th, 1945, the maharajahs met at the Taj Mahal. Fighting in India had de facto stopped. Even the religious riots had died down. So it was on November 17th that Sree Chithira Thirunal announced the dissolution of the Kingdom of Travancore and indeed all Princely States. Instead, the maharajahs would become modern European style aristocrats, forming a broad national ruling class but only directly controlling their private holdings and whatever offices they might attain. In their place would rise the Empire of Hindustan and Moslemstan. The now Emperor Thirunal had been deeply impressed by the Tripartite Empire's ability to combine cultural pluralism with religious homogeneity and a fairly strong Kaiser, and based his new Empire on their government. There were two Kingdoms, the Kingdom of Hindustan and the Kingdom of Moslemstan. The Kingdom of Hindustan (OTL India) would be predominantly populated and dominated by Hindus, with some concessions to Sikhs and other non-Muslim minorities. Moslemstan (OTL Pakistan, Kashmir, and Bangladesh) would be run by Muslims in a similar manner. While there were no forced relocations of Muslims or Hindus, the majority would self-segregate into their new kingdoms. Helping this was the fact that Hindus or Muslims living outside their kingdom could not legally vote in the other kingdom's elections. The plan wasn't perfect, but it allowed for stability. However, the new Emperor wasn't done shocking the world.
On November 20th, 1945, he officially signed a treaty of alliance with the Tripartite Empire. At first, this seems like the least likely Great Power for any country to align with, least of all a place as massive as his Indian Empire. However, Emperor Thirunal had picked the Tripartite for a variety of shrewd reasons. Firstly, the Empire had access to the German sphere's globe straddling capital markets. The Tripartite Empire's corporations could raise massive amounts of capital from within this sphere and invest it in India, without actually subjecting India to German investment per se. This denied the German Empire their most convenient excuse for future military intervention into India. Secondly, the Tripartite Empire had world class medical technology, including the polio vaccine. The Imperial regime's popularity steadily grew as Thirunal secured millions of doses of vaccine for India. Thirdly, the Tripartite Empire had a modern military, and advisors would come and train the Indian military for decades. Finally, when India desired to assert itself, they could easily break the ties that bind without risking a violent war, which a larger power might be willing to fight. India's new Emperor was hell-bent on building the old Raj into a superpower, and this would be the first step.
Indian troops in surplus German uniforms (1945)
Hindus living in now-Moslemstan leave for Hindustan (1946)
Indian sepoys pose during the Second Sepoy Rebellion (1943)