While considering Mutiny of 1857 as the first war of Independence, we generally accept Mangal Pandey as the first martyr of Indian freedom struggle. However, there were many others who revolted (against British) even before 1857. Elucidate the role of some of such unsung heroes whose martyrdom / revolt pre-dates 1857.

There were several uprisings before 1857 such as Sanyasi and Fakir rebellion, Paika Rebelion, Santhal rebellion and so on; each of them led by many unsung heroes. This apart, there were many Indians including employees of Rajas and Nawabs who died during the course of annexation of Indian territories inch by inch. First name among such martyrs is of Raja Nadakumar who was executed for reporting the misdeeds of Warren Hastings to the council, which was overruled by the Governor General.  For Warren Hastings, conviction and execution of Nandakumar was not very difficult as Sir Elijah Imphey, the first chief Justice of the Supreme Court was his close friend.
Second name among such unknown pre 1857 martyrs is of Puli Thevar, considered to be one of the earliest opponents and first chieftain to resist British rule.  He was a local chieftain at Nelkatumseval in modern Tirunelveli  in Tamil Nadu. In 1757-58, when Mohammed Ali, the Nawab of the Carnatic, supported by British tried to extend his control over his area, the poligars rebelled led by Puli Thevar. He was able to forge alliances with others to revolt again the Nawab. The Nawab had to seek support of British to crush the rebellion. Though Puli Thevar was not martyred yet, he had died after spending five or six years in the wilderness.  Third such name is Binda who led a sepoy mutiny in Barrackpur in 1824. The sepoys had taboos of going into sea and were not provided enough facilities to carry their belongings. They revolted but their revolt was immediately crushed, killing some 200 sepoys includfing their leader Binda.  Fourth such name is of Bakshi Jagabandhu Bidyadhar, the military chieftain of the King of Khurda, who led army of Paikas forcing the East India Company forces to retreat.