Hazrat Abu-al Ḥasan Ali bin Usman Al-Hajveri (RA), known as "Data Gunj Bukhsh, was Gaznian (Afghanistan) mystic, theologian, and preacher who became famous for composing the Kashf-al-Maḥjub (Unveiling of the Hidden), a book on Sufism in Persian language. Hazrat Syed Ali Hajveri (RA) is believed to have contributed "significantly" to the spread of Islam in South Asia through his preaching, with historians describing him as "one of the most important figures to have spread Islam in the Indian subcontinent."
Hazrat Syed Ali Hajveri (RA) is venerated as the patron saint of Lahore, Pakistan. He is, moreover, one of the most widely venerated saints in the entire Indian subcontinent, and his shrine is in Lahore, popularly known as "Data Darbar", is one of the most frequented shrines in South Asia. At present, it is Pakistan's largest shrine in numbers of annual visitors and in the size of the shrine complex. It was nationalized in 1960, is managed today by the Department of Auqaf and Religious Affairs Punjab.
Hazrat Syed Ali Hajveri (RA) was born in Ghazni, in present-day Afghanistan. He is a direct descendant of Holy Prophet Muhammad (PBUH) through his father who was a direct descendant of Imam Hasan ibn Ali (RA). His genealogical chain goes back eight generations to Hazrat Ali (RA). According to the autobiographical information recorded in his own Kashf-al-maḥjub, it is evident that Hazrat Ali Hajveri (RA) travelled widely through the Ghaznavid Empire and beyond, spending considerable time in Baghdad, Nishapur, and Damascus, where he met many of the pre-eminent Ṣufis of his time. In matters of jurisprudence, he received training in the Hanafi rite of orthodox Sunni law under various teachers. As for his Sufi training, he was linked through his teacher Hazrat Abu-al Fazal al-Khuttali (RA) to Hazrat Al-Husri (RA), Hazrat Abu Bakr Shibli (RA) (d.946 AD), and Hazrat Junayd Baghdadi (RA) (d.910 AD). Eventually, Hazrat Ali Hajveri (RA) settled in Lahore, where he died in 1072 AD/5465 AH with the reputation of a renowned preacher and teacher. After his death, he was unanimously regarded as a great saint by popular acclaim.