The teaching or tradition, which we call Buddhism, arose from the Buddha's experience of Enlightenment more than 2,500 years ago. It is thus with the Buddha that Buddhism began.
It is natural that we would ask "Who is the Buddha?" The first thing we have to note is that the word "Buddha" is not a name, but rather a title. The Buddha means "The Awakened One" or "He who Knows"
The one whom we call "the Buddha" lived in where we call Nepal today, in the foothills of the Himalayas. His father, Shuddhodana Gautama was King of a clan called the Sakya. The Queen was on her way to her father's kingdom when she gave birth to the Buddha to be. He was given the name Siddhartha.
As Prince Siddhartha grew up, he was given, by the standard of those days, the best education and is said to have performed exceptionally well in all areas. And at the age of 16, he was married to Yashodhara. (It was customary to marry young.)
As a prince, we would expect him to live a luxurious life and he did. But despite his well-to-do way of life, he was deeply dissatisfied. The Buddhist Scriptures spoke of a kind of spiritual crisis, a turning point, when the Prince saw the Four Signs (an old man, sick man, dead man and an ascetic). He was deeply troubled by the suffering all people have to go through. They caused him to reflect on the problem of suffering.
He thus felt a need to find the answer for himself. He also felt that he had to leave the palace and luxurious life to find the answer. And this was what he did.
For the next 6 years, he travelled from place to place seeking teachers who could show him the way. But as none could, he decided to seek the answer by himself. There was then a popular practice of extreme asceticism. It is believed that one can realise the truth by torturing the physical body. And that is what Siddhartha did. However, after 6 years of hard practice, he could not find the answer. Knowing that it was no the way to the Truth, he had the courage to give it up.
Finally, he found himself a beautiful spot beside a river and sat under the shade of a great Bodhi tree. There he sat and made a resolution, "I will not rise from this spot until I am Fully Enlightened". So day after day, night after night, he sat in deep meditation. With his mind concentrated and controlled, he purified his mind and looked deep into the nature of all phenomena. On Vesak night, the night of the full moon of May, just as he was gazing upon the rising morning star, full illumination, full Enlightenment arose.
The Prince Siddhartha Gautama, had become the Buddha.