The Hindu nationalism (Hindutva) is a political concept based on Hinduism. The ideals of Hindu nationalists are against the secularization of India (separation of church and state) to protect the Hindu values. The Hindu nationalists follow the agenda to create a "Hindu Rashtra" in India with "Hindu Rastravada" (Hindu law), revival of Sanskrit, reconversion of former Hindus, reconquest of lost territories of ancient India which is called as "Akhand Bharat" and traditional belong to Hindus. Hindu nationalism is a protection mechanism Hinduism itself is a peaceful religion that respects differences and recognizes all the concepts. The reason for the radical development in Hinduism has its origins in Islamic and Colonial India. It is a known fact that humans or animals become hostile when they feel threatened. The Hindus felt threatened by the foreign invasions and by this fear, despair and anger manifest the Hindu nationalism. The Hindu nationalism and Muslim hostility is much stronger in North India than in South India, because the northern part of India has suffered a long time under the Islamic occupation physically and emotionally, the Hindus feared for their existence. The Hindu nationalism rise and flourished under the saffron flag of the Maratha Empire. The Hindu nationalists were active during the colonial period and after independence. Opponents of Hindu nationalism Not all Hindus agree with the concept of Hindu nationalism, It is criticized by various groups for violating the Indian coexistence and radicalization of Hinduism. Some Hindus complain that Hindu nationalism does not represent all Hindu traditions or it support caste system. The acts of violence by Hindu nationalists are referred by international medias as "saffron terror".