Siddhārtha Gautama (Sanskrit; Pali: Siddhattha Gotama) was a spiritual teacher from ancient India and the founder of Buddhism. He is generally recognized by Buddhists as the Supreme Buddha (Sammāsambuddha) of our age. The time of his birth and death are uncertain: most early 20th-century historians date his lifetime from c. 563 BCE to 483 BCE; more recently, however, at a specialist symposium on this question, the majority of those scholars who presented definite opinions gave dates within 20 years either side of 400 BCE for the Buddha's death, with others supporting earlier or later dates.

Gautama, also known as Śākyamuni or Shakyamuni ("sage of the Shakyas"), is the key figure in Buddhism, and accounts of his life, discourses, and monastic rules were said to have been summarized after his death and memorized by the . Passed down by oral tradition, the , the collection of teachings attributed to Gautama by the Theravada, was committed to writing about 400 years later. "Scholars are increasingly reluctant to make unqualified claims about the historical facts of the Buddha's life and teachings.