How did the Bodhi tree came to be associated with the Buddha and
Buddhism? The affinity can be traced back to more then 2500 years ago
with the Bodhisattva's (Buddha-to-be) search for Enlightenment.
The Bodhisattva was born Prince Siddhartha, son of the ruler of a small kingdom in ancient northern India. His people were called the Shakyans. He lived a life of great comfort and luxury and was to become the King. But all these changed when he saw the "four divine messengers". The first three messangers or sights were Old Age, Sickness and Death. It was through the three sights that the Prince, still at the prime of his youth, learnt about the realities of life, whereupon he learnt about suffering and discovered compassion.
The fourth sight that he saw was a Holy Man, an ascetic who has given up all of life's possessions and dedicated himself to seeking Enlightenment. The Prince knew that with all the distractions and temptations of his current life, he would not be able to dedicate himself fully to the same task. He decided to cast off his former status and possessions, and dedicated his life to seeking an answer to transcend all suffering in life. From that time on, the Prince was formally known as the Bodhisattva, one who seeks Enlightenment for the sake of all.
The Bodhisattva started out learning from various teachers, but none could point the way out of suffering to him. He then practised extreme asceticism, as it was believed by some that that was the way to liberation. The Bodhisattva almost died of exhaustion and starvation due to the harsh practice, but did find what he was looking for either. It was at this point that he realised that abundant sense pleasures and extreme asceticiism are both not conducive to the spiritual life. He thus discovered the Middle Path of balance and moderation. Remembering a meditative experience he had while he was a child, he decided to explore that path.
The Bodhisattva started eating again and regained his former health. He then put his full efforts into the practice of meditation. He sat under a Bo tree to shelter himself from the elements and entered deep meditation, wherein he was able to attain a concentrated, bright and purified mind. The Bodhisattva then directed his mind to understanding suffering, its cause, its end, and the path that led to its end. By the third watch of the night, he found what he was seeking. With newfound understanding, Ignorance was destroyed; knowledge arose; darkness was destroyed; light arose. Having attained liberation (of mind from suffering), the Bodhisattva was henceforth known as the Buddha, the Awakened One. The Bo tree under which he sat came to be known as the Bodhi Tree, the Tree of Enlightenment.
The Buddha was then 35 years of age. He dedicated the rest of his life to sharing the Dharma (the teaching of Truth) to those who were willing to learn. His missionary work lasted 45 years and by the time of his passing into final Nirvana, there was already a large monastic order and community of lay supporters who dedicated their lives to practice of the Dharma. Even then, there was already the practice of reverence to the Bodhi Tree as a symbol of the Buddha and his Enlightenment.
The above is a short write-up on the biography of the Buddha. For those who would like to learn more details about his life and what he taught, the following websites are recommended -