The idea of Islam had never been indigenous in the Indian subcontinent. It was as alien to Indians as aliens are to humanity today. The first association of Islam with Hinduism or specifically with India took place during the 8th Century AD. The Persian text Chach Nama(translated by Mirza Kalichbeg Fredunbeg) narrates the story of the governor of Iraq, Hajjaj helping some people captured by pirates in the region of Debal, now known as Karachi. The governor sent a large cavalry under the leadership of Muhammad bin-Qasim who afterward resorted to attacking Sindhis, Jats, Hindu, and Buddhist kings and looted wealth after desecrating the temples.
It was Muhammad bin-Qasim who made the people of non-Islamic religion pay jizya in place of religious freedom. With Muhammad-bin-Qasim started the persecution of Hindus in the Indian subcontinent and this went on until the fall of the Moghul empire.
In his book named “Theory and Practice of Muslim State in India”, Historian K S Lal claims that the population of the Indian subcontinent decreased from 200 million to 170 million between 1000-1500 AD and it further decreased to 120 million during the establishment of the Moghuls. The main reason K S Lal cited was killing, deportations, and wars. The Muslim rulers attacked the temples and educational institutions of the Hindus and with the killings of the Hindu kings, the ideology of Hinduism started to decline.
Moghul rulers like Akbar let only the Brahmanical education thrive and that Brahmanism became the definition of Hinduism in modern India. The Vedic Philosophy got almost destroyed and the decline of Sanskrit led to the flourishing of regional languages.
With persecution came the forceful conversion of Hindus into Islam. This was actually advised by the Kajis and muftis to these Muslim rulers. Kaji Mughisuddin of Bayánah told Alauddin Khilji “the Prophet has commanded us to slay them, plunder them, and make them captive; saying – convert them to Islam or kill them, enslave them and spoil their wealth and property” (source-Wikipedia).
From Mahmud to Timur, Babur to Aurgazeb the Muslim rulers always resorted to persecution and forceful conversion because of the hollowness of Islam. In a letter to Sri Kalidas Nag, Gurudev Rabindranath Tagore said, “ They(Muslims and Christians) are not satisfied with just observing their own religions but are determined to destroy all other religions. That’s why the only way to make peace with them is to embrace their religion”
To be precise, mention may be made of the rule of Tipu Sultan in Kerala. His rule was one of conversion and killings. He took the help of the Mapilla Muslims in order to carry out conversions. In his book, “Kerala under Haidar Ali and Tipu Sultan” C.K.Kareem pointed out that Tipu Sultan even issued an edict to destroy Hindu Temples. The Hindus living there were called Kodava Hindus. They were either forcefully circumcised or killed if opposed. The number of death may vary but according to various historians, the number ranged between 70000 to 95000.
The same thing continued even after that. Hindus in different parts of India were either converted or killed. A large number of conversions took place in Mapilla riots, Partition of India, Direct Action Day, Noakhali Riots, Killing of Kashmiri Pandits. Such instances took place all around the Indian subcontinent (source-Wikipedia).
Islam had no base in India. Most of the Indian Muslims were once a Hindu before they had been forced or trapped to follow Islam. The traps are many. Some groups distribute free Quran and Pamphlets, some try to find similarities between the two religions, some organize lectures by Zakir Naik, some resort to Love Jihad, etc. The process is ongoing but the facts remain the same that every Indian Muslim had a Hindu ancestor.
Since these Indian Muslims were once Hindus they never resort to attacking their fellow Hindu brothers but the conflict arises when the idea of worldwide Islam permeates into their clan. Swami Vivekananda himself validated the point as is found in the book “The Complete Works of Swami Vivekananda”. The great saint declared, “Mohammedanism in India is quite a different thing from that in any other country. It is only when Mohammedans come from other countries and preach to their co-religionists in India about living with men who are not of their faith that a Mohammedan mob is aroused and fights.”
Thus, these Indian Muslims should understand their past and start the journey back to Hinduism because Hinduism is the oldest living religion in the world and is regarded as the mother of every religion. With the disappearance of Hinduism, the whole world will move towards destruction that could never be stopped. In the words of Rishi Aurobindo, “That which we call the Hindu religion is really the Eternal religion because it embraces all others.” (Aurobindo’s Letters, Volume II)