Reasons for the martyrdom of Guru Arjan

Guru Arjun Dev ji was martyred in 1606 by Mughal Authorities. There are several reason of his martyrdom, which are explained below:

1. Creation of Adi Granth: This was the basic and main reason of his martyrdom. Guru Arjun Dev ji collected Bani's of all devotees (Hindu Muslims, Upper Caste, Lower Caste etc.) and put into Guru Granth Sahib, which makes one proper institution of Gurmat, which have totally new philosphy and was against many philosphies of Hinduism and Islam. Many people started following this philosphy. Even Saint like Saint Mian Mir became friends and Mureed of Gurmat. This stunned the Mughal Government. All the High Muslim priests and Hindu priests were against the philosphy of Guru Granth Sahib. Jahangir even showed his hatered in his book Tuzak-e-jahangiri in which he wrote that many fool muslims also started following arjun dev and he want to bring arjun dev in his religion.
2. Minas: Minas was against Guru Arjun Dev from starting they and High Hindu priests started playing tactics against Guru Arjun Dev.
3. Governer Chandu Shah: He also became hostile of Guru Arjun Dev as Guru Arjun Dev ji rejected his proposal of marriage, for his daughter. Sikh Sangat at that time forced Guru Arjun Dev ji to not accept this proposal as they were against tactics of Chandu, whose aim was to misuse Guru Ghar after marriage.
4. 'Sheikh Ahmed Sirhindi: It is also Said that Sheikh Ahmad Sarhindi was very much revered by Muslims. He presented himself to be Islam's Prophet of the second millennium; the first millennium belonging to Prophet Muhammad. He asserted that his status was higher than the Sikh Gurus. This was emphatically rejected by Guru Arjan Dev Ji. Sheikh Ahmad had great influence on Jehangir. Citing the Guru’s blessings bestowed upon Prince Khusro he instigated the Emperor against Guru Arjan Dev Ji. Jehangir wrote in his biography: A Hindu named Arjan lived at Goindwal...simple minded Hindus and ignorant and foolish Muslims have been persuaded to adopt his ways... this business has been flourishing for three generations. For a long time it had been in my mind to put a stop to this affair or to bring him into the fold of Islam...