Swami Vivekananda was born in an aristocratic Bengali kayastha family of Calcutta on January 12, 1863. Vivekananda's parents influenced his thinking—his father by his rationality and his mother by her religious temperament. From his childhood, he showed an inclination towards spirituality and God realization. His guru, Ramakrishna, taught him Advaita Vedanta (non-dualism); that all religions are true and that service to man was the most effective worship of God.
After the death of his Guru, Vivekananda became a wandering monk, touring the Indian subcontinent and acquiring first-hand knowledge of conditions in India. He later traveled to Chicago and represented India as a delegate in the 1893 Parliament of World Religions. He conducted hundreds of public and private lectures and classes, disseminating Vedanta and Yoga in America, England and Europe. He also established the Vedanta societies in America and England.