The Upanishads are a part of the Vedas and are ancient Sanskrit texts that contain some of the central philosophical concepts and ideas of Hinduism, some of which are shared with Buddhism, and Jainism.
In India, Islamic rulers Qutb-ud-din Aibak imposed jizya on non-Muslims first time which was called kharaj-o-jizya. Jizya was abolished by the Mughal ruler Akbar in the 16th century but was re-introduced by Aurangzeb in the 17th century.