The International Society for Krishna Consciousness (ISKCON), known colloquially as the Hare Krishna movement or Hare Krishnas, is a Gaudiya Vaishnava religious organisation. ISKCON was founded in 1966 in New York City by Srila A.C. Bhaktivedanta Swami Prabhupada. Its core beliefs are based on Hindu scriptures, particularly the Bhagavad Gita and the Bhagavata Purana, and the Gaudiya Vaishnava tradition, which has had adherents in India since the late 15th century and American and European devotees since the early 1900s.
ISKCON devotees follow a disciplic line of Brahma Madhva Gaudiya Bhagavata Vaishnavas and are the largest branch of Gaudiya Vaishnavism. Vaishnavism means 'worship of Vishnu', and Gauḍa refers to the area where this particular branch of Vaishnavism originated, in the Gauda region of West Bengal. Gaudiya Vaishnavism has had a following in India, especially West Bengal and Odisha for the past five hundred years. Gaudiya Vaishnavism was founded by the saint Sri Chaitanya Mahaprabhu who rapidly spread his form of ecstatic bhakti (devotion) throughout Bengal. He established Sankirtan, the practice of publicly expressing devotion to Lord Krishna, the Supreme God, through dance and song. This form of communal worship responded to rigid caste structures by engaging all people in worship regardless of caste and creed. Chaitanya emphasized chanting the Hare Krishna Mahamantra (the 'great mantra'). According to many shastric sources, He is considered by the Gaudiya Vaishnavas to be a direct incarnation of God, Krishna himself.