World War I began with an unprecedented outpouring of loyalty and goodwill towards the United Kingdom from within the mainstream political leadership , contrary to initial British fears of an Indian revolt . India contributed massively to the British war effort by providing men and resources . About 1.3 million Indian soldiers and labourers served in Europe , Africa , and the Middle East , while both the Indian government and the princes sent large supplies of food , money , and ammunition . However , Bengal and Punjab remained hotbeds of anti colonial activities . Terrorism in Bengal , increasingly closely linked with the unrests in Punjab , was significant enough to nearly paralyse the regional administration . With outlines of German links with the Indian revolutionary movement already in place as early as 1912 , the main conspiracy was formulated between the Ghadar Party in United States , the Berlin Committee in Germany , Indian revolutionary underground in India , Sinn Féin and the German Foreign Office through the consulate in San Francisco at the beginning of World War I . A number of failed attempts were made at mutiny , among them the February mutiny plan and the Singapore mutiny . This movement was suppressed by means of a massive international counter-intelligence operation and draconian political acts ( including the Defence of India act 1915 ) that lasted nearly ten years . Other notable events that formed a part of the conspiracy include the Annie Larsen arms plot , the Mission to Kabul that also attempted to rally Afghanistan against British India . The Mutiny of the Connaught Rangers in India , as well as by some accounts , the Black Tom explosion in 1916 are also considered minor events linked to the conspiracy
Black Tom explosion
Black Tom explosion
Revolutionary movement for Indian independence