Thanks to Yashwantji!
How the glorious tradition of Nalanda came to an end is descrobed vividly by historian Sukumara Datta in his Buddhist Monks and Monasteries of India, 1962.
Here are some extracts from the book.
The end of Buddhist institutions in North India
To this long and varied history of the Sangha in India, there was an end - swift and sudden, full of terror and pity, like the denouement of a tragic drama. The Sangha did not survive perhaps more than a decade the storm and violence of Muslim inroads and conquests in northern India. Lapsed into complete quiescence elsewhere in India, its last accents were still being whispered from the monastic towers of Bihar and Bengal, while round the north of the region, the Khiliji hordes were gathering as for a cloudburst. They were fast sweeping down south. These mid-Asian tribesmen had seen no edifices in their desert home-land and knew but little about architectural styles and distinctions. The tall towers of the monasteries, soaring above the circuit-walls, arrested attention; they easily caused the buildings to be mistaken for military fastnesses: so the monasteries became targets of fierce attack.
After the razing of the Odantapura monastery in AD 1199 by Ikhtiyar Khiliji's soldiers, it was discovered by the marauders that inside were only heaps of books and no hidden arms or treasures and that the place was merely a madrdsa (educational establishment) and not a fort. But all the monks had been killed and there was no one to explain to the victors what the books were about. Wholesale massacre was the order of the day; monks and monasteries perished together in a terrible holocaust.
Yet a handful of survivors was left in the trail of the general destruction. They dispersed and fled with their cherished treasures- a few bundles of holy texts hugged in the bosom and concealed under the sanghati (monk's outer robe). They wandered away to remote, secluded monasteries, far out of the invader's track; or to the nearest seaports to take ship and sail away to Arakan or Burma. But most of them wended their way northwards towards the eastern Himaalayas. Danger dogged their footsteps until, crossing the Himalayan foothills or stealing farther north along the high wind-swept mountain-passes, the hunted found security at last in the more hospitable countries of Nepal and Tibet.
Thus came about the final dispersal of the Buddhist Sangha in India. The Moving Finger wrote finis to its history round the turn of the thirteenth century and, having writ, moved on.
The Last Days of nalanda
We know on historical evidence that Odantapura Mahavihara was sacked and razed to the ground round 1198. Round 1234, when Dharmasvami visited it, Odantapura was Muslim military head-quarters.2 Nalanda, only about six miles off, may have been after the sack of Odantapura a target of attack by roving bands of Muslim soldiery. But this mahavihara was not demolished like Odantapura and Vikramasila, though, as Taranatha says, much damage was done with the result that many monks deserted it. But the very last report about its condition after the worst had been done by the ravagers, coming from an eye-witness, the Tibetan monk Dharmasvami, shows that Nalanda, though doomed to death, was fated not to die, for teaching and learning was going on here over at least four after-decades.
But what a Nalanda it was! like the strange nightmare of Hsuan-tsang six centuries back when Nalanda was in all its glory brought up by the whirligig of time.
Yet even then the ghost of past magnificence loomed darkly over the desolation. There were still to be seen -seven great lofty pinnacles (Sikharas)- and out to the north, fourteen.3 Eighty small viharas, damaged by the Turaskas and deserted by monks, were still there and, beyond, as many as eight hundred. The guess could not, however, have been numerically precise. It is impossible to say when this crop of small viharas had gone up; Dharrnasvami says only that a Raja. and his queen had built them - probably not very long before the Turaska threat descended. Archaeologists have discovered no trace of them: they were probably of flimsy construction.
But somewhere in this melancholy mass of decayed and deserted buildings, a lingering pulse of life feebly went on.
Somewhere here a nonogenarian monk-teacher, named Rahula Sribhadra,5 had made his dwelling and taught Sanskrit grammar to seventy students. He was in the last stage of poverty and decrepitude. He lived on a small allowance for food given by a Brahmana lay disciple named Jayadeva who lived at Odantapura. Time and again came threats of an impending raid from the military head-quarters there. Jayadeva himself became a suspect. In the midst of these alarms, he was suddenly arrested and thrown into a military prison at Odantapura. While in captivity, he came to learn that a fresh raid on Nalanda was brewing and managed to transmit a message of warning to his master advising him to flee post-haste. By then everyone had left Nalanda except the old man and his Tibetan disciple. Not caring for the little remainder of his own life, the master urged his pupil to save himself by quick flight from the approaching danger. Eventually, however the pupil's entreaties prevailing both decided to quit. They went the pupil carrying the master on his back along with a small supply of rice, sugar and a few books to the Temple of Jnananatha at some distance and hid themselves. While they remained in hiding, 300 Muslim soldiers arrived, armed and ready for the assault. The mid came and passed over. Then the two refugees stole out of their hiding place back again to Nalanda.
Dharmasvami says that the Tibetan pupil could after all complete his studies and, after a brief stay, left the place with the teacher's permission. The libraries had perished long, long ago; Dharmasvami could not get a scrap of manuscript to copy, though some of the monks there possessed a few manuscripts.6
Dharmasvaynt mentions Odantapura in his travel-record twice as the residence of a Tnraska military commander (see Biography of Dharmasvarnin, Intro., p. xlii.)
3 Roerichs Biography of .Dharmasvamin (pub. by K. P. Jayaswal Research Institute, Patna, 1959), p. 91.
4 Dharnaasvami's reference may be to Raja Buddhasena of Magadha who is said by him to have fled from Gaya into a jungle at the time of Turaska raid on Gaya and returned when the raid was over. He is said to have been a patron of the Nalanda teacher and his pupils (see Biography of .Dharmasvjmin, p. 90).
5 Rahula _Sribhadra's name was probably known in Tibet through Dharrnasvamis narrative, for Taranatha gives precisely the same information about Sribhadra and states the number of his pupils as seventy, as told by Dharmasvami (see Biiogr'phy of Dharmasvamin, Altekar's Intro., p. vi).
6 This thrilling account of the last days of Nalanda is taken from a Tibetah text kept in a monastery of central Tibet of which a photostatic copy was brought by Rahula Sankrityayana and left to be edited and translated with the K. P. Jayaswal Research Institute of Patna. The text is entitled Biography of Chag lo-tsa-ba Chos-rje-dpal-the Tibetan name of Dharmasvami. It was evidently written by a disciple under his dictation. This Tibetan monk-pilgrim visited some districts of eastern India and was in Bihar in 1234-36. He records in the work his experiences in the country. The work has been edited with an accompanying English translation by Dr G. Roerich (Moscow) and published by the Institute. Dharmasvami's account of Nalanda is contained in Chapter X (pp. 90 ff.).
Five of the Leaves from an Ashtasahasrika Prajnaparamita Manuscipt
Click here if you cannot see it http://www.askasia.org/images/teachers/display/498.jpg
India, Bihar, Nalanda monastery; Pala period (c.8th - 12th century)
Ink and opaque watercolor on palm leaf
Each, approx., H. 2 7/8 in. (7.3 cm); W. 22 3/8 in. (56.8 cm)
Mr. and Mrs. John D. Rockefeller 3rd Acquisitions Fund
The Buddha Shakyamuni's life story was codified by artists and philosophers into eight standard scenes which both encapsulate the Buddha's biography and provide a model spiritual life for the devotee. Known as the "Eight Great Events," the scenes depict (from left to right, excluding the central deities): the Buddha's miraculous birth from the side of his mother, Maya; his victory over Mara, the god of death and desire; his first sermon; a miracle he performed at Shravasti in which he multiplied himself; his descent from the heaven of thirty-three gods; his taming of the rampaging elephant Nalagiri; the offering of honey by a monkey; and finally, his death. The central images of each leaf represent specific deities (from top to bottom): the goddess Prajnaparamita, the Bodhisattva Manjushri, the Bodhisattva Avalokiteshvara, and the goddess Tara. This manuscript is particularly important because of the inscriptions on leaf E, which record, in Sanskrit and Tibetan, the history of the manuscript from its creation at the famous Nalanda monastery in India through its use in Tibet by the compiler of the first Tibetan canon of Buddhism, Buton, to its dedication for the benefit of a Tibetan nobleman as part of his funeral rites. These inscriptions illustrate how Buddhist manuscripts helped spread both Buddhism and its imagery from India to other parts of Asia.