Shri Krishna Chaitanya Mahaprabhu (IAST: Śrī Kṛṣṇa Caitanya Mahāprabhu), honorific: "Mahāprabhu" ("Great Lord"), (18 February 1486 – 14 June 1533), was an Indian guru considered by his followers to be the Supreme Personality of Godhead and the chief proponent of the Achintya Bheda Abheda (Inconceivable Difference/One-ness) Vedanta school and the Gaudiya Vaishnavism tradition within Hinduism. He also expounded the Vaishnava school of Bhakti yoga (meaning loving devotion to God), based on Bhagavata Purana and Bhagavad Gita. Of various forms and direct or indirect expansions of Krishna such as Lord Narasimha (Man-Lion; Krishna in mood of anger), Mahavishnu and Garbhodaksayi Vishnu respectively, he is believed to be Krishna in the mood of Radha. He popularised the chanting of the 'Hare Krishna mantra' and composed the Siksastakam (eight devotional prayers) in Sanskrit. His followers, Gaudiya Vaishnavas, revere him as a Krishna with the mood and complexion of his source of inspiration Radha. His birthday is celebrated as Gaura-purnima. Chaitanya is sometimes referred to by the names Gauranga or Gaura due to his fair complexion, and Nimai due to his being born underneath a Neem tree.

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