GURBILĀS PĀTSHĀHĪ 10, a poeticized account of Gurū Gobind Siṅgh's career, was completed in 1751, forty-three years after his death. Until it was published in 1968, there were only four manuscript copies of the work known to exist. Apart from specialists, very few had heard of it. The author of this work is Kuir Siṅgh, a resident of Mohallā Kamboāṅ of a city, which, in his book, remains unspecified, but which could possibly be Lahore. He entered the fold of the Khālsā under the influence of Bhāī Manī Siṅgh. He uses two noms de plume for himself, namely Bisan Hari/ Visanu Hari and Srī Kant Hari. The practice of using in the text synonyms of the actual name was fairly common amongst medieval Hindi poets. But the terms Kuir Siṅgh employs have no semantic relationship with his name. It is likely that he adopted the new name Bishan Siṅgh (synonym: Bisan Hari) on receiving the rites of Khālsā baptism.
The entire Gurbilās is written in verse of various forms, including aṛil, salok, savaīyā, sirkhaṇḍī, soraṭhā, kabit, chaupaī, Jhūlaṇā, tribhaṅgī, dohirā, bhujaṅg, rasāval, gīā, and narāj. Out of a total of 2, 938 chhands, 2, 901 are written in Braj Bhāṣā and the remaining 37 in Punjabi. The work has a few specimens of prose interspersed in the text which are linguistically very significant. As far his sources of information, the poet seems to have had access to two preceding works, Gurū Gobind Siṅgh's Bachitra Nāṭak and Saināpati's Srī Gur Sobhā. More than that, he has relied on information personally obtained from Bhāī Manī Siṅgh.
Whereas the Bachitra Nāṭak comes down to 1696 and the Srī Gur Sobhā takes up the thread in a broad way from where it ends, Kuir Siṅgh's Gurbilās covers the entire span of Gurū Gobind Siṅgh's life. It is the first work to record details of the early years of his career, of the Sīs Bheṭ episode in the creation of the Khālsā, and the march of the Gurū from Chamkaur to Talvaṇḍī Sābo. It also contains reference to Gurū Gobind Siṅgh passing on the spiritual succession to the Gurū Granth Sāhib which was to be the Gurū after him. Equally important is the poet's evocation of Gurū Gobind Siṅgh's image. Writing at a time when the Sikhs were engaged in a bitter struggle against the Mughal rulers, he portrays the Gurū as a liberator and warrior, and as the guardian angel of the Khālsā ranks. The Gurū's mission, nebulously hinted at in the Bachitra Nāṭak, is now clearly understood as the extirpation of the tyrannical rule of the Mughals and the establishment of an autonomous Khālsā rāj. A devotee and admirer of Gurū Gobind Siṅgh, he addresses him by such terms as Prabhū (Master), Kartār (Creator), Karunāsindh (Ocean of Compassion), Dayānidh (Treasure of Grace), Kripāsindh (Ocean of Kindness), etc.
The Gurbilās is not, however, free from faults. Its dates are often erroneous; for instance, 1689, instead of 1699 for the creation of the Khālsā and 1709 instead of 1708 for the death of Gurū Gobind Siṅgh at Nāndeḍ. Figures concerning the strength of enemy forces and the casualties suffered by them are grossly exaggerated. The battles of Anandpur are divided into two rounds, the first of which is described as preceding the attacks of Dilāwar Khān, Husain Khān and Mirzā Beg, which is historically incorrect. Similarly, Gurū Gobind Siṅgh's journey to the South with Emperor Bahādur Shāh is unhistorically interrupted by long visits, lasting for years, to places like Paṭnā, Kāshī and Ayodhyā.
A notable feature of the work is the evidence it furnishes about the martyrdom of Bhāī Manī Siṅgh and his companions in 1734. Kuir Siṅgh seems to have been an eyewitness and mentions the names of some of the Sikhs who were executed along with Bhāī Manī Siṅgh. No other contemporary source contains this information.