<P> A major cause of resentment that arose ten months prior to the outbreak of the rebellion was the General Service Enlistment Act of 25 July 1856 . As noted above, men of the Bengal Army had been exempted from overseas service . Specifically, they were enlisted only for service in territories to which they could march . Governor - General Lord Dalhousie saw this as an anomaly, since all sepoys of the Madras and Bombay Armies and the six "General Service" battalions of the Bengal Army had accepted an obligation to serve overseas if required . As a result, the burden of providing contingents for active service in Burma, readily accessible only by sea, and China had fallen disproportionately on the two smaller Presidency Armies . As signed into effect by Lord Canning, Dalhousie's successor as Governor - General, the act required only new recruits to the Bengal Army to accept a commitment for general service . However, serving high - caste sepoys were fearful that it would be eventually extended to them, as well as preventing sons following fathers into an army with a strong tradition of family service . </P> <P> There were also grievances over the issue of promotions, based on seniority . This, as well as the increasing number of European officers in the battalions, made promotion slow, and many Indian officers did not reach commissioned rank until they were too old to be effective . </P> <P> The final spark was provided by the ammunition for the new Enfield P - 53 rifle . These rifles, which fired Minié balls, had a tighter fit than the earlier muskets, and used paper cartridges that came pre-greased . To load the rifle, sepoys had to bite the cartridge open to release the powder . The grease used on these cartridges was rumoured to include tallow derived from beef, which would be offensive to Hindus, and pork, which would be offensive to Muslims . At least one Company official pointed out the difficulties this may cause: </P> <P> unless it be proven that the grease employed in these cartridges is not of a nature to offend or interfere with the prejudices of caste, it will be expedient not to issue them for test to Native corps . </P>

150th anniversary of armed uprising in indian army against the british emperor was celebrated in