The Ghadar Mutiny (Hindustani: ग़दर राज्य-क्रान्ति, غدر ریاست - کرانتی Ġadara Rājya-krānti), also known as the Ghadar Conspiracy, was a plan to initiate a pan-Indian mutiny in the British Indian Army in February 1915 to end the British Raj in India. The plot originated at the onset of the First World War, between the Ghadar Party in the United States, the Berlin Committee in Germany, the Indian revolutionary underground in British India and the German Foreign Office through the consulate in San Francisco. The incident derives its name from the North American Ghadar Party, whose members of the Punjabi Sikh community in Canada and United States were among the most prominent participants in the plan. It was the most prominent amongst a number of plans of the much larger Hindu–German Mutiny, formulated between 1914 and 1917 to initiate a Pan-Indian rebellion against the British Raj during World War I. The mutiny was planned to start in the key state of Punjab, followed by mutinies in Bengal and rest of India. Indian units as far as Singapore were planned to participate in the rebellion. The plans were thwarted through a coordinated intelligence and police response. British intelligence infiltrated the Ghadarite movement in Canada and in India, and last minute intelligence from a spy helping to crush the planned uprising in Punjab before it started. Key figures were arrested, mutinies in smaller units and garrisons within India were also crushed.
Intelligence about the threat of the mutiny led to a number of important war-time measures introduced in India, including the passages of Ingress into India Ordinance, 1914, the Foreigners act 1914, and the Defence of India Act 1915. The conspiracy was followed by the First Lahore Conspiracy Trial and Benares Conspiracy Trial which saw death sentences awarded to a number of Indian revolutionaries, and exile to a number of others. After the end of the war, fear of a second Ghadarite uprising led to the recommendations of the Rowlatt Acts and thence the Jallianwallah Bagh Massacre.