Thailand is probably the most purely Buddhist nation in the world with over 95% of its population adhering to Buddhism. It’s a country that is filled with lavish Buddhist history and culture. As soon as you enter the country from Bangkok the capital to Chiang Mai in  the  North you  can   see the influence of Buddhism all around
 
you from the thousands of beautiful and elaborate temples, monks collecting alms before dawn to the many and varied Buddhist festivals that happen throughout the year. Thailand is a country that is steeped in rich heritage and culture that is inextricably linked to Buddhism and Buddhist ways.

                  Buddhism was introduced into Thailand, some twenty-three centuries ago, when the region was still populated by Mons and Lawas. Nakhon Pathom was then the administrative center and, after the advent of the religion, became an active seat of Buddhist propagation. Later the region was occupied by the Thais, also followers of Buddhism; Khun Luang Mao, who ruled over the Ailao Kingdom about two thousand years ago, was the first Thai Buddhist king and the professed upholder of the religion.

                  Mahayana Buddhism spread to Thailand in the 9th century during the reign of the Srivijaya kings, who ruled from Sumatra (Indonesia) and whose territories extended over some southern provinces of Thailand. Meanwhile the Khmer (Cambodia) authority and influence also spread over the whole of central and North Eastern Thailand. The Khmer kings were adherents of Mahayana Buddhism, which had by then absorbed much of the Brahmanistic elements into its system. It was around this time that Mahayana Buddhism and Brahmanism began to exert deep influence on the Thai culture. Although neither of them came to replace Theravada Buddhism, their cultural influences were considerable, and can be readily observed even today.
 

                  Another stream of cultural and religious influences began to flow into Thailand from Myanmar (Burma) around the 11th century when King Anuruddha ascended the Myanmar throne. His territorial conquests stretched as far as the Thai kingdoms of Lanna and Lanchang. Another form of Theravada Buddhism, called Pukam or Pagan Buddhism, which was practiced by the Myanmar people, spread into these lands. Following the decline of the Khmer and Myanmar influences, there emerged in the 13th century the kingdoms of Lanna in the north and Sukhothai in north-central Thailand. At the height of its glory Lanna became an important seat of Buddhist learning, where numerous scholarly works in Pali were produced.

                  The most famous king of Sukhothai   was  Ramkamhaeng  the Great,
  
 
who unified the Thai people under one single rule and whose territories extended far and wide. He strongly supported the form of Theravada Buddhism prevalent in Sri Lanka, which by then had spread to Thailand following a general reform under the auspices of King Parakramabahu the Great. Lanka Buddhism, as it was called, became highly popular in Thailand and virtually replaced other forms of Buddhism in the country. This is the form of Buddhism preserved and practiced in the present time. Later, during the Ayutthaya period, when religious conditions in Sri Lanka deteriorated so much that not a single monk could be found on the island, Thailand had the opportunity to more than repay this spiritual debt. A delegation of monks, headed by Venerable Upali, was dispatched to Sri Lanka to help revive the monastic order in that country. The ecclesiastical lineage so reestablished became known as the Siam Sect, the country's largest denomination today.

 
 
 
                  Thus the history of Thai Buddhism may be divided into four periods. The first was Theravada Buddhism as introduced by Ashoka's mission; the second was Mahayana Buddhism under the Srivijaya and Khmer influences; the third was Pukam Buddhism introduced from Myanmar, and the fourth, Theravada Buddhism from Sri Lanka. Today Theravada Buddhism is the Buddhism that exists within Thailand although as with many other things in life this is highly complex with many different facets interspersed with various folktales and local religious beliefs.