Pre-modern persecutions of Buddhism
In 224 CE Zoroastrianism was made the official religion of the Persia, and other religions were not tolerated, thus halting the spread of Buddhism westwards. In the 3rd century the Sassanids overran the Bactrian region, overthrowing Kushan rule, were persecuted with many of their stupas fired. Although strong supporters of Zoroastrianism, the Sassanids tolerated Buddhism and allowed the construction of more Buddhist monasteries. It was during their rule that the Lokottaravada followers erected the two Buddha statues at Bamiyan.
During the second half of the third century, the Zoroastrian high priest Kirder dominated the religious policy of the state. He ordered the destruction of several Buddhist monasteries in Afghanistan, since the amalgam of Buddhism and Zoroastrianism manifested in the form of a "Buddha-Mazda" deity appeared to him as heresy. Buddhism quickly recovered after his death.
The first alleged persecution of Buddhists in India took place in the 2nd century BC by King Pushyamitra Shunga. A non-contemporary Buddhist text states that Pushyamitra cruelly persecuted Buddhists. While some scholars believe he did persecute Buddhists based on the Buddhist accounts, others consider them biased because of him not patronising them. Many other scholars have expressed skepticism about the Buddhist claims. Étienne Lamotte points out that the Buddhist legends are not consistent about the location of Pushyamitra's anti-Buddhist campaign and his death: "To judge from the documents, Pushyamitra must be acquitted through lack of proof." Agreeing with him, D. Devahuti states that Pushyamitra's sudden destruction after offering rewards for Buddhist heads is "manifestly false". R. C. Mitra states that "The tales of persecution by Pushyamitra as recorded in Divyavadana and by Taranatha bear marks of evident absurdity."
Central Asian and North Western Indian Buddhism weakened in the 6th century following the White Hun invasion who followed their own religions such as Tengri and Manichaean. Around 440 CE they conquered Sogdiana then conquered Gandhara and pushed on into the Gangetic Plains. Their King Mihirkula who ruled from 515 CE suppressed Buddhism, destroying monasteries as far as modern-day Allahabad before his son reversed the policy.
Persecution by Hindus
Dharmarajika stupa in Sarnath once stood 30 m tall before demolition in 1794
Persecution of Buddhism started as early as in the life or soon after the death of King Ashoka. D.N. Jha writes that according to Kashmiri texts dated to the 12th century, Ashoka's Son Jalauka was shaivite and was responsible for the destruction of many Buddhist monasteries. The story of Jalauka is essentially legendary, and no independent corroboration of the Kashmir tradition has been discovered. Patanjali, a famous grammarian stated in his Mahabhashya that Brahmins and Sharamanas (buddhists) were eternal enemies With the emergence of Hindu rulers of the Gupta Empire, Hinduism saw a major revivalism in the Indian subcontinent which challenged Buddhism which was at that time at its zenith. Even though Gupta empire was tolerant towards Buddhism and patronized Buddhist arts and religious institutions, Hindu revivalism generally became a major threat to Buddhism which led to its decline. A Buddhist illustrated palm leaf manuscript from Pala period (one of the earliest Indian illustrated manuscripts to survive in modern times) is preserved in University of Cambridge library. Composed in the year 1015, the manuscript contains a note from the year 1138 by a Buddhist believer called Karunavajra which indicates that without his efforts, the manuscript would have been destroyed during a political struggle for power. The note states that 'he rescued the 'Perfection of Wisdom, incomparable Mother of the Omniscient' from falling into the hands of unbelievers (who according to Camillo Formigatti were most probably people of Brahmanical affiliation). In 1794 Jagat Singh, Dewan (minister) of Raja Chet Singh of Banaras began excavating two pre Ashokan era stupas at Sarnath for construction material. Dharmarajika stupa was completely demolished and only its foundation exists today while Dhamekh stupa incurred serious damage. During excavation a green marble relic casket was discovered from Dharmarajika stupa which contained Buddha's ashes was subsequently thrown into Ganges river by Jagat Singh according to his Hindu faith. The incident was reported by a British resident and timely action of British authorities saved Dhamekh Stupa from demolition.
Emperor Wuzong of Tang
Emperor Wuzong of Tang (814-846) indulged in indiscriminate religious persecution, solving a financial crisis by seizing the property of Buddhist monasteries. Buddhism had developed into a major religious force in China during the Tang period, and its monasteries had tax-exempt status. Wuzong closed many Buddhist shrines, confiscated their property, and sent the monks and nuns home to lay life. Apart from economic reasons, Wuzong's motivation was also philosophical or ideological. As a zealous Taoist, he considered Buddhism a foreign religion that was harmful to Chinese society. He went after other foreign religions as well, all but eradicating Zoroastrianism and Manichaeism in China, and his persecution of the growing Nestorian Christian churches sent Chinese Christianity into a decline from which it never recovered.
King Langdarma of Tibet
Langdarma was a Tibetan King, who reigned from 838-841 CE. He is believed to have been anti-Buddhist and a follower of the Bön religion.
The Oirats (Western Mongols) converted to Tibetan Buddhism around 1615. The Dzungars were a confederation of several Oirat tribes that emerged suddenly in the early 17th century. The Dzungar Khanate was the last great nomadic empire in Asia. In the 18th century, the Dzungars were annihilated by Qianlong Emperor in several campaigns. About 80% of the Dzungar population, or around 500,000 to 800,000 people, were killed during or after the Zunghar Genocide by Manchu Bannermen and Khalkha Mongols during the Manchu conquest in 1755-1757.
The Kalmyk Khanate was founded in the 17th century with Tibetan Buddhism as its main religion, following the earlier migration of the Oirats from Dzungaria through Central Asia to the steppe around the mouth of the Volga River. During the course of the 18th century, they were absorbed by the Russian Empire, which was then expanding to the south and east. The Russian Orthodox church pressured many Kalmyks to adopt Orthodoxy. In the winter of 1770-1771, about 300,000 Kalmyks set out to return to China. Their goal was to retake control of Dzungaria from the Qing dynasty of China. Along the way many were attacked and killed by Kazakhs and Kyrgyz, their historical enemies based on intertribal competition for land, and many more died of starvation and disease. After several months of travel, only one-third of the original group reached Dzungaria and had no choice but to surrender to the Qing upon arrival.