The History of Butter Lamp Festival
The Festival began in the 7th year of Yongle in the Ming Dynasty (1409). It was created by Tsongkhapa, the founder of the Gelug Sect of Tibetan Buddhism when he founded the Dharma Meeting in Lhasa on the fifteenth day of the first month of the Tibetan calendar.
Butter lamps or butterlamps
(Tibetan: དཀར་མེ་, Wylie: dkar me; simplified Chinese: 酥油灯; traditional Chinese: 酥油燈; pinyin: sūyóu dēng) are a common feature of Tibetan Buddhist temples and monasteries throughout the Himalayas. The lamps traditionally burn clarified yak butter, but now often use vegetable oil or vanaspati ghee.
According to the Root tantra of Cakrasaṃvara Tantra, "If you wish for sublime realization, offer hundreds of lights". Pilgrims also supply lamp oil to gain merit. Externally, the lights are seen to banish darkness.