No one quite knows who built the fort – there are very few written sources that mention it and even the ones that do provide very little or no information about the its builders. It gets a passing mention in works such as the 17th century Ferishta’s Tarikh-i-Ferishta and Ma’aisir-i Alamgiri, the extensive biography of Aurangzeb. The latter mentions a fort called “Mangal” that was built by an ancestor of a “Dev Rai’.
A Chronological Layout of Golconda. Drawn by Cornelia Wu. Source: Foundations of Golconda and the Rise of Fortifications in the Fourteenth-Century Deccan
These, along with other equally cryptic pieces of information, lead historians to believe that the Golconda fort was built in the 13th century by the Kakatiyas of Warangal. We then zero in on Ganapati Deva as the most probable builder of this once-insignificant fort, but there isn’t much of his original fortress left at Golconda. A closer look, however, will indicate that the granite walls of the Bala Hisar are from that period – they marked the birth of a monument that defined, in more ways than one, the destiny of this region and its people for over four centuries. But more on that later. We’re now in the 13th Century where Golconda is probably just an outpost for the Kakatiya kingdom – Warangal is where it’s all at.
Marika Sardar. (2007). Golconda Through Time: A Mirror of the Evolving Deccan.
Marika Sardar. Foundations of Golconda and the Rise of Fortifications in the Fourteenth-Century Deccan. South Asian Studies Vol. 27, Iss. 1, 2011.