Siddhartha Gautama was a spiritual teacher from ancient India who founded Buddhism. In most Buddhist traditions, he is regarded as the Supreme Buddha of our age, Buddha meaning awakened one or the enlightened one. The time of his birth and death are uncertain: most early 20th-century historians dated his lifetime as c. 563 BCE to 483 BCE, but more recent opinion dates his death to between 486 and 483 BCE or, according to some, between 411 and 400 BCE. Gautama, also kwn as Sakyamuni ( Sage of the Sakyas ), is the primary figure in Buddhism, and accounts of his life, discourses, and monastic rules are believed by Buddhists to have been summarized after his death and memorized by his followers. Various collections of teachings attributed to him were passed down by oral tradition, and first committed to writing about 400 years later.