Gautam Buddha left the royal palace at the age of 29 and went into the jungles of "Gaya" but he could not find peace any where. At last one night he got spiritual knowledge while sitting under a tree.
Siddhartha Gautama was born in 563 BCE (Cousins, 1996) in Lumbini (i.e. in modern-day Nepal) and raised in the small principality of Kapilavastu. His father was King Suddhodana, the leader of the Shakya clan. His mother, Queen Maha Maya, was a Koliyan princess who died during his birth. The infant was given the name Siddhartha, meaning “he who achieves his aim” (Buddha Dharma Education Association, Inc. [BDEA] & BuddhaNet, 2008A, para. 1). After his mother’s death, Siddhartha was brought up by his aunt, his mother's younger sister (and another of his father’s wives), Maha Pajapati (Narada, 1992, p. 14). It is said that Suddhodana, wishing for his son to be a great and mighty king, shielded Siddhartha for many years from religious teachings as well as from the knowledge of human suffering (Thaper, 2002, p. 137).
It is the general opinion of scholars that Siddhartha spent approximately 29 years as a prince in Kapilavastu (Conze, 1959; Gayatso, 2007; Hirakawa & Groner, 2007; Thaper, 2002). Although his father ensured that he was provided with everything he could want or need, Buddhist scriptures say Siddhartha felt that material wealth was not and should not be life's ultimate goal (Narada, 1992, p.14). Therefore, he left the palace to meet his subjects, whereby he came across a person who puzzled him greatly – an elderly man. As told in this story, when his charioteer explained that all people grow old, the prince’s curiosity drove him to make subsequent trips well beyond the palace. On several of these, he encountered a diseased man, a decaying corpse, and a wandering ascetic monk. It is said that upon witnessing these human frailties, Siddhartha became depressed and initially strove to overcome the suffering imposed by ageing, sickness, and death by choosing the lifestyle of an ascetic (Conze, 1959, pp. 39-40).
Siddhartha abandoned his crown for the life of a mendicant in an event known traditionally as the “Great Departure” (Narada, 1992, p. 16). He initially went to Rajagaha and began his ascetic existence by begging for alms in the street, but later left to study under two different hermit teachers. After mastering the teachings of Alara Kalama, Siddhartha was asked to succeed him. However, he felt dissatisfied and incomplete, and moved on to become a student of Udaka Ramaputta. Under his tutelage, it is said that Siddhartha achieved high levels of meditative consciousness. He was once again offered the succession of his teacher, but refused once more to continue on his search for knowledge (Narada, 1992, pp. 19-20).
It is reported that Siddhartha and a group of five companions set out to push the quest for knowledge even further. They supposed that the path to Enlightenment was through self-mortification; they therefore lived as extreme ascetics, denying themselves food and shelter. Buddhist scriptures state that after nearly starving himself to death by restricting his food intake to a single bite per day, Siddhartha collapsed in a river while bathing and very nearly drowned. At this time, he began to reconsider his path, remembering a moment in childhood during which he had been watching his father begin the season's plowing. He attained a deeply concentrated, focused state both blissful and refreshing – the jhāna (Conze, 1959, pp. 47-5
According to early Buddhist texts, after realizing that meditative jhāna was the true path to Awakening and that extreme asceticism did not work, Siddhartha discovered what Buddhists call the “Middle Way” (or the “Noble Eightfold Path”) – a course of moderation away from the extremes of both self-indulgence and self-mortification (Bhikkhu Thanissaro, 2010C). Starved and weakened, he accepted milk and rice pudding from a village girl named Sujata. Afterwards, it has been stated that Siddhartha sat beneath a pipal tree in Bodh Gaya, India, where he vowed never to arise until he had discovered the Truth. Believing that Siddhartha had abandoned his search for knowledge and become undisciplined, his companions left. After a reputed 49 days of meditation and at the age of 35, Siddhartha is said to have attained Enlightenment. From that time forward, he was known to his followers as the Buddha or “Awakened One” (also the “Enlightened One”). He is often referred to in Buddhism as Shakyamuni Buddha, or “Awakened One of the Shakya Clan” (Gyatso, 2007, pp. 8-11).
According to a story in the Āyācana Sutta, Samyutta Nikaya VI.1 – a scripture found in the Pāli and other canons – immediately after his Awakening, the Buddha debated whether or not he should teach the Dharma (or “life path”) to others. He was concerned that human beings were so overpowered by ignorance, greed, and hatred that they could never recognize the path, which is subtle, deep, and hard to grasp. However, in the story, Brahmā Sahampati argued that at least some will understand, which makes the attempt worthwhile in and of itself. The Buddha eventually relented and agreed to teach (Hirakawa & Groner, 2007, p. 119).