As Buddhism spread through Asia, it formed distinct streams of thought and practice: the Theravada ("The Way of the Elders" in South and Southeast Asia), the Mahayana (the “Great Vehicle” in East Asia), and the Vajrayana (the “Diamond Vehicle” in Tibet), a distinctive and vibrant form of Mahayana Buddhism that now has a substantial following.
In India, Buddhism began to wane in the 6th and 7th centuries CE when devotional Hinduism replaced Buddhism in the south and Hephthalite Huns invaded and sacked monasteries in the north. By the 13th century, repeated invasions by the Turks ensured that Buddhism had virtually disappeared. By this time, however, Buddhism was flourishing in many other parts of Asia. As early as the 3rd century BCE the Indian emperor Ashoka, a convert to Buddhism, is said to have established the tradition on the island of Ceylon, or Sri Lanka. By the 5th century CE, Buddhism had spread throughout what are now Myanmar and Thailand. By the 13th century CE, one of the early Buddhist schools, called the Theravada, “the way of the elders,” had become the dominant tradition of South and Southeast Asia.
As early as the 1st century CE, Buddhist monks made their way over the “Silk Road” through Central Asia to China. By the 7th century CE, Buddhism had made a significant impact in China, interacting with Confucian and Daoist cultures and ideas. By this time the tradition was also firmly established in Korea. In the 6th century CE, the Buddhist tradition was also introduced into Japan, where it developed in a milieu shaped by both Shintō and other indigenous traditions. This form of Buddhism that first developed in India and later flourished in East Asia is known as the Mahayana, or “Great Vehicle.”
In the 8th century, Buddhism, shaped by the Tantric traditions of northeast India, spread to the high mountain plateau of Tibet. There, in interaction with the indigenous Bon religion, and with forms of Buddhism that had traveled to Tibet from East Asia, a distinctive and vibrant form of Mahayana Buddhism emerged known as Vajrayana, the “Diamond Vehicle.”
These streams of Buddhism are differentiated to some extent by their interpretations of the Buddha and the Buddha’s teachings, the scriptures they hold in special reverence, and the variety of cultural expressions they lend to Buddhist life and practice. It would be a mistake, however, to identify these streams of tradition too rigidly with either specific ideas or specific geographical areas.