Nalanda University , the renowned ancient Mahavihara in Bihar, India, was destroyed by fire around 1193-1200 CE, an event largely attributed to Turkic invader Bakhtiyar Khilji. The destruction occurred during Khilji's military campaigns in the region, aimed at consolidating power. The assault saw the university's massive library, known as Dharmaganja (comprising three large multi-story buildings named Ratnasagara, Ratnodadhi, and Ratnaranjaka), set ablaze.
Reports, including those referencing the Persian historian Minhaj-i-Siraj in Tabaqat-i Nasiri, suggest the library housed millions of precious manuscripts covering philosophy, astronomy, medicine, and Buddhist studies. The library reportedly burned for several months, with thick smoke hanging over the region for days, destroying irreplaceable knowledge.
Alongside the library, monks and scholars were massacred, and the monastery buildings were demolished, dealing a massive blow to Buddhist education in India.
While this was not the first time Nalanda faced destruction-earlier damages occurred in the 5th and 7th centuries - the late 12th-century invasion resulted in its final, irreversible decline, turning the flourishing international intellectual hub into ruins.
The site remained largely forgotten until its excavation.