Buddha's Birthday is a holiday traditionally celebrated in Mahayana Buddhism to commemorate the birth of the Prince Siddhartha Gautama, later the Gautama Buddha and founder of Buddhism.
According to the Theravada Tripitaka scriptures At the age of thirty five, He attained enlightenment (nirvana) underneath a Bodhi tree at Bodhgaya (modern day India). At the age of eighty, He died at Kushinagar, India.
Buddhists go to common Viharas to observe a rather longer-than-usual, full-length Buddhist sutra, akin to a service. Informally called "Buddha's Birthday", it actually commemorates the birth, enlightenment (nirvāna), and death (Parinirvāna) of Gautama Buddha in the Theravada tradition.In China and Korea, it is celebrated on the eighth day of the fourth month in the Chinese lunar calendar.The date varies from year to year in the Western Gregorian calendar, but usually falls in April or May. In Tibet, it falls on the 7th day of the fourth month of the Tibetan calendar (in May).The bathing of the Buddha is a major feature of Buddha's birthday celebrations in the city.India is the land where the Buddha attained enlightenment (nirvana) at Bodhgaya and established Buddhism.
In South Asian and Southeast Asian countries, Buddha's birthday is celebrated on the full moon day of the Vaisakha month of the Buddhist calendar and the Hindu calendar, which usually falls in April or May month of the Western Gregorian calendar.