Hinduism

Hinduism is the main religion of the Indian subcontinent. In Toaru Majutsu no Index, Hinduism and Hindu mythology are used as a base for Magic, primarily by Indian cabals.

Principles
It should be noted  that Hinduism encompasses a wide range of beliefs and is not bound by a single doctrine. By no means can the entirety of Hindu beliefs be summarized; as it is easily the most complex religion in the history of the world. For example, there is no one leader of the religion, equivalent to the Pope or the, so there are different sects of the religion with different dogmas.

Contrary to popular Western belief, most modern Hindus will attest that it is monotheistic, not polytheistic. In the same way Christianity has the concept of the Father, Son, and Holy Spirit being different forms of the same God, Hinduism has a similar belief: Vishnu, Lakshmi, Lord Shiva, Bramha, Hanuman, etc. are all different forms of one God, known variously as Brahma, Ishvara, or other names. So, though Hindu Mythology contains a vast pantheon of gods and beings, they are all recognized to be part of the same Ishvara or "All-Being", i.e, God. This is not set in stone, and debates on whereas Hinduism is polytheistic or monotheistic have occurred for centuries.

Hinduism is also very loose and allows acceptance of other religions; the practice of Hinduic ideals and beliefs, known as , is defined as "a way of life", and not a religion. This makes Hinduism the only major world religion that is by nature, i.e, involving devotion to one God while accepting the existence of others.

History
Hinduism's roots can be traced back to Iron Age India, and as such it is believed to be the oldest living religion in the world.

Uses of Hinduism & Hindu Mythology in the story

 * Astra: Supernatural weapons associated with Hindu deities.
 * The Gate of the Gods Come from the Heavens make use of downsized versions of the Astras.
 * Garuda: A mythical bird, appearing in both Hindu and Buddhist mythologies, the mount of Vishnu.
 * A spiritual item based on the Garuda is used by members of Gate of the Gods Come from the Heavens for reconnaissance.
 * Vishnu: The supreme deity of Vaishnavism, and part of the Trimurti together with Brahma and Shiva, representing preservation.
 * Marian Slingeneyer uses Dáinsleif to summon Vishnu Avatara, an amalgamation of Vishnu's avatars, by cutting away the Amaravati Phase.

Users of Hindu-based Magic

 * Laksha
 * Harisha
 * Gate of the Gods Come from the Heavens