To quote Will Durant’s famous line:
“The Islamic conquest of India is probably the bloodiest story in history. It is a discouraging tale, for its evident moral is that civilization is a precious good, whose delicate complex of order and freedom, culture and peace, can at any moment be overthrown by barbarians invading from without or multiplying within.” (Story of Civilization, vol.1, Our Oriental Heritage, New York 1972, p.459)
Today’s Muslims cannot help it that other Muslims did certain things in 712 or 1565 or 1971. One thing they can do, however, is to critically reread their scripture to discern the doctrinal factors of Muslim violence against Hindus and Hinduism. Of course, even without scriptural injunction, people get violent and wage wars; if Mahmud Ghaznavi hadn’t come, some of the people he killed would have died in other, non-religious conflicts. But the basic Quranic doctrine of hatred against the unbelievers has also encouraged many good-natured and pious people to take up the sword against Hindus and other Pagans, not because they couldn’t control their aggressive instincts, but because they had been told that killing unbelievers was a meritorious act. Good people have perpetrated evil because religious authorities had depicted it as good.
https://www.raoulwallenberg.net/news/was-there-an-islamic-“genocide”-of-hindus/
There is no official estimate of the total death toll of Hindus at the hands of Islam. A first glance at important testimonies by Muslim chroniclers suggests that, over 13 centuries and a territory as vast as the Subcontinent, Muslim Holy Warriors easily killed more Hindus than the 6 million of the Holocaust. Ferishtha lists several occasions when the Bahmani sultans in central India (1347-1528) killed a hundred thousand Hindus, which they set as a minimum goal whenever they felt like “punishing” the Hindus; and they were only a third-rank provincial dynasty. The biggest slaughters took place during the raids of Mahmud Ghaznavi (ca. 1000 CE); during the actual conquest of North India by Mohammed Ghori and his lieutenants (1192 ff.); and under the Delhi Sultanate (1206-1526). The Moghuls (1526-1857), even Babar and Aurangzeb, were fairly restrained tyrants by comparison. Prof. K.S. Lal once estimated that the Indian population declined by 50 million under the Sultanate, but that would be hard to substantiate; research into the magnitude of the damage Islam did to India is yet to start in right earnest.
Note that attempts are made to deny this history. In Indian schoolbooks and the media, an idyllic picture of Hindu-Muslim harmony in the pre-British period is propagated in outright contradiction with the testimony of the primary sources. Like Holocaust denial, this propaganda can be called negationism. The really daring negationists don’t just deny the crimes against Hindus, they invert the picture and blame the Hindus themselves. Thus, it is routinely alleged that Hindus persecuted and destroyed Buddhism; in reality, Buddhist monasteries and universities flourished under Hindu rule, but their thousands of monks were killed by Ghori and his lieutenants.
Apart from actual killing, millions of Hindus disappeared by way of enslavement. After every conquest by a Muslim invader, slave markets in Bagdad and Samarkand were flooded with Hindus. Slaves were likely to die of hardship, e.g. the mountain range Hindu Koh, “Indian mountain”, was renamed Hindu Kush, “Hindu-killer”, when one cold night in the reign of Timur Lenk (1398-99), a hundred thousand Hindu slaves died there while on transport to Central Asia. Though Timur conquered Delhi from another Muslim ruler, he recorded in his journal that he made sure his pillaging soldiers spared the Muslim quarter, while in the Hindu areas, they took “twenty slaves each”. Hindu slaves were converted to Islam, and when their descendants gained their freedom, they swelled the numbers of the Muslim community. It is a cruel twist of history that the Muslims who forced Partition on India were partly the progeny of Hindus enslaved by Islam.
mass killing of Hindus by Muslims rarely took place in peacetime, but typically in the fervour immediately following military victories, e.g. the fall of the metropolis of Vijayanagar in 1565 was “celebrated” with a general massacre and arson. Once Muslim power was established, Muslim rulers sought to exploit and humiliate rather than kill the Hindus, and discourage rebellion by making some sort of compromise. Not that peacetime was all that peaceful, for as Fernand Braudel wrote in A History of Civilizations (Penguin 1988/1963, p.232-236), Islamic rule in India as a “colonial experiment” was “extremely violent”, and “the Muslims could not rule the country except by systematic terror. Cruelty was the norm — burnings, summary executions, crucifixions or impalements, inventive tortures. Hindu temples were destroyed to make way for mosques. On occasion there were forced conversions. If ever there were an uprising, it was instantly and savagely repressed: houses were burned, the countryside was laid waste, men were slaughtered and women were taken as slaves.”
Though all these small acts of terror added up to a death toll of genocidal proportions, no organized genocide of the Holocaust type took place. One constraint on Muslim zeal for Holy War was the endemic inter-Muslim warfare and intrigue (no history of a royal house was bloodier than that of the Delhi Sultanate 1206-1525), another the prevalence of the Hanifite school of Islamic law in India. This is the only one among the four law schools in Sunni Islam which allows Pagans to subsist as zimmis, dis-empowered third-class citizens paying a special tax for the favour of being tolerated; the other three schools of jurisprudence ruled that Pagans, as opposed to Christians and Jews, had to be given a choice between Islam and death.
Staggering numbers also died as collateral damage of the deliberate impoverishment by Sultans like Alauddin Khilji and Jahangir. As Braudel put it: “The levies it had to pay were so crushing that one catastrophic harvest was enough to unleash famines and epidemics capable of killing a million people at a time. Appalling poverty was the constant counterpart of the conquerors’ opulence.”
versus:
https://en.wikipedia.org/wiki/List_of_genocides_by_death_toll