Title of the first 10 leaders of Sikhism .
The first was Nanak , who before his death (1539) began the tradition that allowed the Guru to name his successor. He was followed by Angad (1539–1552), Amar Das , Ramdas (1574–1581), Arjan , Hargobind , Hari Rai , Hari Krishen (1661–1664), Tegh Bahadur (1664–1675), and Gobind Singh . In time the Guru became as much a military as a spiritual leader. Gobind Singh discontinued the office in 1708 and vested its authority in the Sikh sacred scripture, the Adi Granth . See also guru .