Bhai Langah is a well-known figure in early Sikh history, was originally a follower of Sultan Sakhi Sarwar. His father Abu ul-Khair was a Muslim convert dhillon Jat, belonging to the village of Jhabal, in the present Amritsar district of the Punjab, he was one of the three chaudharies or revenue officials of the parganah of Patti, who between them were responsible for collecting on behalf of the governor of Lahore, a revenue of Rs 900,000 from villages under their jurisdiction. Since all of the relatives of Abu Ul-Khair were Sikhs or Hindus we can safely deduce that the title/jurisdiction of Chaudhary was acquired after he converted to Islam.
Langah alone had 84 villages under him. It is said that once Langah was afflicted with a serious illness. Neither medicine nor prayer to the patron saint of his sect, Sakhi Sarwar, proved of any avail. He met a Sikh who counselled him to pray to God Almighty and to Guru Nanak. Langah soon recovered and was converted a Sikh. He lovingly contributed the labour of his hands as well as money for the excavataion of the sacred pool and the construction of Harmandir at Amritsar.
His devotion and earestness were applauded by Guru Arjan, who appointed him a masand (officiant) in his own area. He was one of the privileged Sikhs who were included in the marriage party of Guru Hargobind in 1604. Langah, again, was one of the five Sikhs chosen to accompany Guru Arjan on his last journey to LAhore. He witnessed the torturous scenes leading to the Guru's martyrdom. He continued to enjoy the confidence of the next Guru, Guru Hargobind. Known for his fighting skills as well as his religious faith and piety, Bhai Langah was appointed one of the commanders of Guru Hargobind's newly trained force. Later, when the Guru visited Lahore and had a small shrine constructed on the spot where Guru Arjan's body had been cremated, Bhai Langah was appointed to look after it. He served in this capacity for many a long year. Bhai Langah died at Dhilvan, on the bank of the River Beas.
Among Bhai Langah's descendants was the Sikh General, Baghel Singh of Karorsinghia misl, who triumphantly entered Delhi in 1770 and had several Sikh shrines erected to mark the historical sites in the capital. Mai Bhago, who fought with the Majha contingent in tthe battle of Khidrana (present-day Muktsar), was the granddaughter of Bhai Langah's younger brother Piro Shah.