China is home to the largest number of Buddhists, with approximately 50% of the religion's world-wide population within its borders, according to a 2010 study by the Pew Research Center. Thailand comes in second with 13%, followed by Japan and Burma which have 9% and 8% respectively. Less than 1% of the population in the U.S. is Buddhist.
Buddhism started in the fifth century in India, when Siddhartha Gautama observed the world´s suffering and set out to find a solution. Gautama was born into a Royal family in what is now Nepal, but realized that wealth did not guarantee happiness. For six years he studied different teachings, religions and philosophies, until he found the "middle path" and was enlightened.
Known as the Buddha, he spent the rest of his life teaching others about the path he had found, in what would become a religion (or way of life) for over 488 million people.