Sister (Bhagini) Nivedita born Margaret Elizabeth Noble (28 October 1867 – 13 October 1911) was a Scots-Irish social worker, author, teacher and a disciple of Swami Vivekananda. She spent her childhood and early days of her youth in Ireland. From her father, from her college professor etc. she learned many valuable lessons like – service to mankind is the true service to God. She worked as school teacher and later also opened a school. She was committed to marry a Welsh youth who died soon after engagement.
Sister Nivedita met Swami Vivekananda in 1895 in London and traveled to Calcutta, India (present-day Kolkata) in 1898. Swami Vivekananda gave her the name Nivedita (meaning "Dedicated to God") when he initiated her into the vow of Brahmacharya on 25 March 1898. In November 1898, she opened a girls' school in Bagbazar area of Calcutta. She wanted to educate those girls who were deprived of even basic education. During the plague epidemic in Calcutta in 1899 Nivedita nursed and took care of the poor patients.
Nivedita had close associations with the newly established Ramakrishna Mission. However, because of her active contribution in the field of Indian Nationalism, she had to publicly dissociate herself from the activities of the Ramakrishna Mission under the then president Swami Brahmananda. She was very intimate with Sarada Devi, the spiritual consort of Ramakrishna and one of the major influences behind Ramakrishna Mission and also with all brother disciples of Swami Vivekananda. She died on 13 October 1911 in Darjeeling. Her epitaph reads, "Here reposes Sister Nivedita who gave her all to India".