Swami Vivekananda, known in his pre-monastic life as Narendra Nath Datta, was born in an affluent family in Kolkata on 12 January 1863. His father, Vishwanath Datta, was a successful attorney with interests in a wide range of subjects, and his mother, Bhuvaneshwari Devi, was endowed with deep devotion, strong character and other qualities. A precocious boy, Narendra excelled in music, gymnastics and studies. By the time he graduated from Calcutta University, he had acquired a vast knowledge of different subjects, especially Western philosophy and history. He was a major force in the revival of Hinduism in India, and contributed to the concept of nationalism in colonial India. Vivekananda founded the Ramakrishna Math and the Ramakrishna Mission. Vivekananda conducted hundreds of public and private lectures and classes, disseminating tenets of Hindu philosophy in the United States, England and Europe. In India, Vivekananda is regarded as a patriotic saint and his birthday is celebrated there as National Youth Day.