Arya Samaj was founded by Swami Dayananda Saraswati in 1875 to reform Hindu society and promote Vedic teachings. He emphasized the authority of the Vedas and opposed idol worship, caste discrimination, and child marriage. Swami Vivekananda founded Ramakrishna Mission, while Keshav Chandra Sen and Ishwar Chandra Vidyasagar were associated with Brahmo Samaj and social reform movements in Bengal.