The Royal Indian Navy mutiny was a failed insurrection of Indian naval ratings, soldiers, police personnel and civilians against the British government in India in February 1946. From the initial flashpoint in Bombay (now Mumbai), the revolt spread and found support throughout British India, from Karachi to Calcutta (now Kolkata), and ultimately came to involve over 10,000 sailors in 56 ships and shore establishments. The mutiny failed to turn into a revolution because sailors were asked to surrender after the British authorities had assembled superior forces to suppress the mutiny.

The mutiny ended with the surrender of revolting RIN sailors to British authorities. The Indian National Congress and the Muslim League convinced Indian sailors to surrender and condemned the mutiny, realising the political and military risks of unrest of this nature on the eve of independence. The leaders of the Congress were of the view that their idea of a peaceful culmination to a freedom struggle and smooth transfer of power would have been lost if an armed revolt succeeded with undesirable consequences. The Communist Party of India was the only nation–wide political organisation that supported the rebellion. The British authorities had later branded the Naval Mutiny as a "larger communist conspiracy raging from the Middle East to the Far East against the British crown".

The RIN Revolt started as a strike by ratings of the Royal Indian Navy on 18 February in protest against general conditions. The immediate issues of the revolt were living conditions and food. By dusk on 19 February, a Naval Central Strike committee was elected. The strike found some support amongst the Indian population, though not their political leadership who saw the dangers of mutiny on the eve of Independence. The actions of the mutineers were supported by demonstrations which included a one–day general strike in Bombay. The strike spread to other cities, and was joined by elements of the Royal Indian Air Force and local police forces.

Indian Naval personnel began calling themselves the "Indian National Navy" and offered left–handed salutes to British officers. At some places, NCOs in the British Indian Army ignored and defied orders from British superiors. In Madras (now Chennai) and Poona (now Pune), the British garrisons had to face some unrest within the ranks of the Indian Army. Widespread rioting took place from Karachi to Calcutta. Notably, the revolting ships hoisted three flags tied together – those of the Congress, Muslim League, and the Red Flag of the Communist Party of India (CPI), signifying the unity and downplaying of communal issues among the mutineers.

The revolt was called off following a meeting between the President of the Naval Central Strike Committee (NCSC), M. S. Khan, and Vallab Bhai Patel of the Congress with a guarantee that none would be persecuted. Contingents of the naval ratings were arrested and imprisoned in camps with distressing conditions over the following months, and the condition of surrender which shielded them from persecution. Patel, who had been sent to Bombay to settle the crisis, issued a statement calling on the strikers to end their action, which was later echoed by a statement issued in Calcutta by Muhammad Ali Jinnah on behalf of the Muslim League. Under these considerable pressures, the strikers gave way. Arrests were then made, followed by courts martial and the dismissal of 476 sailors from the Royal Indian Navy. None of those dismissed were reinstated into either the Indian or Pakistani navies after independence.

Background

During the Second World War, the Royal Indian Navy (RIN) had rapidly expanded from a small naval force composed of sloops to become a full–fledged navy. The expansion occurred in an ad hoc basis as operational requirements changed over the course of the war, the naval headquarters was moved from Bombay to New Delhi during this period, the navy acquired a varied assortment of warships and landing crafts, and the naval infrastructure in British India was expanded with improved dockyards, new training facilities and other support infrastructure. The RIN played an instrumental role in halting the progress of Japanese forces in the Indian Ocean Theatre. The force was involved in escorting allied convoys in the Indian Ocean, defending the Indian shoreline against naval invasions and supporting allied military operations through coastlines and rivers during the Burma Campaign.

Due to the war, recruitments began occurring beyond the confines of the "martial races" composed of demographics who were politically segregated. The ratings were composed of a diverse group, from different regions and religions, mostly from rural backgrounds. Some of them had not even physically encountered Britons before the recruitment. Exponential rises in the price of goods, famines and other economic difficulties eventually forced many of them to join the expanding armed forces of the British Raj. In a period of 4 to 6 years, the recruits underwent a transformation in their mindset. They were exposed to developments from around the world.

In 1945, it was ten times larger than its size in 1939. Between 1942 and 1945, the CPI leaders helped in carrying out mass recruitment of Indians especially communist activists into the British Indian Army and RIN for war efforts against Nazi Germany. However once the war was over, the newly recruited men turned against the British government.

Demobilisation The demobilisation of the Royal Indian Navy began once the war with Japan ended. Leased ships were paid off, a number of shore establishments were closed and the sailors were concentrated into select establishments for their release from service. Much of the concentration occurred in the naval establishments at Bombay, which served as the primary base for the RIN and hence became over crowded with bored and dissatisfied personnel awaiting their release. The dissatisfaction among the Indian personnel came from a variety of causes such as dismal living conditions, arbitrary treatment, inadequate pay and a perception of an uncaring senior leadership. Despite the wartime expansion, the officer staff of the formed remained predominantly white and the navy was noted to be the most conservative in terms of number of Indian officers. The concentration of the personnel and grievances in its ranks combined with tense interracial relations and aspirations to end British rule in India led to a volatile situation in the navy.

Unlike the close relationship between British Army and the British Indian Army, the Royal Indian Navy was not privy to such a relationship with the Royal Navy. However the war had brought the two closer together under the leadership of the British High Command and due to temporary transfers between the two navies. The British naval circles were prevalent with perceptions of lack of competency among Indians, opposition to the independence movement and assumptions of continued British presence in India. John Henry Godfrey was the commanding officer of the RIN and had overseen its transformation from a small coastal defense fleet to a regional navy. In the post war period, he intended to preserve its status as a regional navy and had the vision for the RIN to serve as in instrument of British interests in the Indian Ocean. Operating under this vision, Godfrey proposed the acquisition of new warships from the British Admiralty and maintained that British officers would be necessary for the fleet to continue functioning as Indian officers lacked the required expertise and training.

Indian National Army trials The INA trials, the stories of Subhas Chandra Bose ("Netaji"), as well as the stories of INA's fight during the Siege of Imphal and in Burma were seeping into the glaring public–eye at the time. These, received through the wireless sets and the media, fed discontent and ultimately inspired the sailors to strike. After the Second World War, three officers of the Indian National Army (INA), General Shah Nawaz Khan, Colonel Prem Sahgal and Colonel Gurbaksh Singh Dhillon were put on trial at the Red Fort in Delhi for "waging war against the King Emperor", i.e., the Emperor of India.

According to the Home Department of the Raj, the Congress advocacy during the trials, their election campaign for the advisory council and the highlighting of excesses during the Quit India Movement contained inflammatory speeches and had created a volatile atmosphere. There were several upsurges between November 1945 and February 1946. In a September 1945, All India Congress Committee meeting, the party had taken the stand that in case of any confrontations, negotiation and settlement must be the way forward.

Calcutta in particular experienced frequent instances of civil unrest in opposition to the trials, and eventually led to the popular support emerging in favor of the revolutionary vision of an independent India that was advocated by the Communist Party of India.

Unrest in the British forces in India Between 1943 and 1945, the Royal Indian Navy suffered nine mutinies on board various individual ships.

In early February 1946, mutinies broke out in the Indian Pioneers unit stationed in Calcutta, Bengal Province and later at a signals training center at the air base in Jubbulpore, Central Provinces and Berar. According to Francis Tuker, the commanding officer of the Eastern Command, the dissatisfaction against British colonial rule was rapidly growing within the bureaucracy and the police force as well as in the armed forces itself.

HMIS Talwar HMIS Talwar was a shore establishment, with a signals school at Colaba, Bombay. Following the end of the war, the establishment was among the locations in Bombay where a large number of ratings were deployed. Around 1,000 communications operators were residing at the establishment, most of the whom consisted of lower–middle class and middle–class people with matriculation or college education as opposed to general seamen who were primarily from the peasantry. In late 1945, upon reassignment, around 20 operators along with a dozen sympathisers frustrated with racial discrimination faced by them during their period of service, formed a secretive group under the self designation of Azad Hind () and began hatching conspiracies to undermine their senior officers.

The first incident occurred on 1 December 1945, when RIN Commanders had intended to open up the establishment to the public; in the morning the group vandalised the premises by littering the parade ground with burnt flags and bunting, prominently displaying brooms and buckets at the tower and painting slogans such as "Quit India, Down with British Raj", and "Victory to Gandhi and Nehru", across various walls of the establishment. The senior officers cleaned up the premises before the public arrived without further action. The weak response emboldened the conspirators who continued on with similar activities over the course of the following months.

The response was a result of correspondences issued by the Commander–in–Chief Sir Claude Auchinleck informing officers to maintain a degree of tolerance for a smooth transition in case of Indian Independence such that British interests are secured by maintaining good relations. Unable to catch the conspirators and restricted from taking strict action against their underlings, the command at HMIS Talwar resorted to increasing the pace of demobilization in the hopes that the troublemakers would be pushed out of the force during the process. As a result, the group shrunk in size but the remaining ones remained enthused for more nationalistic activities.