Sources give the date of the Buddha's birth as 563 BCE and others as 624 BCE; Theravada Buddhist countries tend to use the latter figure. This displaces all the dates in the following table about 61 years backward in time. See Theravada Buddhism.
There is controversy about the base date of the Buddhist Era, with 544 BCE and 483 BCE being advanced as the date of the parinibbana of the Buddha. As Wilhelm Geiger pointed out, the Sri Lankan chronicles, the Dipavamsa and Mahavamsa are the primary sources for ancient South Asian chronology; they date the consecration (abhisheka) of Asoka to 218 years after the parinibbana. Chandragupta Maurya ascended the throne 56 years prior to this, or 162 years after the parinibbana. The approximate date of Chandragupta's ascension is known to be within two years of 321 BCE (from Megasthenes). Hence the approximate date of the parinibbana is between 485 and 481 BCE - which accords well with the Mahayana dating of 483 BCE.[1]
The difference between the two reckonings seems to have occurred at sometime between the reigns of the Sri Lankan kings Udaya III (946–954 or 1007–1015) and Pârakkama Pandya (c. 1046–1048), when there was considerable unrest in the country.[1]
[edit]BCE
563 BCE: Siddhārtha Gautama, Buddha-to-be, is born in Lumbini into a leading royal family in the republic of the Shakyas, which is now part of Nepal.
534 BCE: Prince Siddhartha goes outside the palace for the first time and sees The Four Sights: an old man, an ill man, a dead man, and a holy man. He is shocked by the first three—he did not know what age, disease, and death were—but is inspired by the holy man to give up his wealth. He leaves his house and lives with three ascetics. However, he wants more than to starve himself, so he becomes a religious teacher.
528 BCE: Siddhartha attains Enlightenment in Buddha Gaya (modern-day Bodhgaya), then travels to a deer park in Sarnath (near Varanasi), India, and begins expounding the Dharma....