Red mda' ba gZhon nu blo gros (1348?1412) played a pivotal role in the history of Tibetan Buddhists' engagement with Indian Madhyamaka philosophy, especially with regard to Candrakirti's interpretation of Nagarjuna. The lasting impact of this historical figure on the shape of Buddhist philosophy in Tibet - and particularly that of Madhyamaka ? has been highly underestimated to date. Red mda' ba was an important teacher of scholastic Buddhist philosophy to the three main founders of Tibetan dGe lugs tradition: Tsong kha pa Blo bzang grags pa (1357?1419), rGyal tshab Dar ma rin chen (1364?1432) and mKhas grub dGe legs dpal bzang (1385?1438). On the basis of his biography, Red mda' ba's contribution to the spiritual culture of Buddhism in his own time can now be analyzed. His biography elucidates, for example, his influence in the upgrading of philosophical studies and dialectics and expanded scholastic education in the monasteries, and his decisive contribution to Tsong kha pa's foundation of the dGe lugs pa school, the lineage to which the Dalai Lamas belong. This work therefore aims to present the first detailed exposition of the life story and legacy of this crucial figure of Tibetan culture and intellectual history. It presents a critical edition and English translation of the biography of Red mda' ba, which had long been lost and was first discovered in 1993 at the China Nationalities Library in Beijing.