He was born as the son of King Chulalongkorn and Queen Sripatcharinthara. When he was only 11 years old, he was sent to study in Cadet school of England and the University of Oxford. Therefore, there is no surprise that Siam then would receive a great deal of Anglo-Saxon cultural heridity. When crown Prince Vajirunahit died, he succeeded him and finally became crowned as the 6th king of the Chakri dynasty on October 23 1910, after his fathers death.

Vajiravudh was the king during the transition from the old to modernized and prosperous Thailand. He continued the modernizations introduced by his father, which was a difficult task due to the great achievements of him. At the end of the reign of Rama VI Siam met a lot of serious problems, many were the setback from the modernization. Siam spent a lot of money for western technology, while got not that much income from exporting the mostly agricultural products. When king Vajiravudh ascended the throne, he was the only hope for the people in the famine and plague stricken country. However, some were disappointed to see the new king barely managed to do the tasks that were essential for the country.

This was most strikely visible when a coup d'etat against him took place on November 11 1924, led by young soldiers. The plot was to seize and force the king to peacefully abdicate, and after that they would urge other princes to take his place as the first President of a Siamese republic. The coup failed; all the accomplice were arrested. Those soldiers thought that the king had nothing to do but write plays and participate in it himself with his favorites. They also accused the king of living a luxurious life in western style; building Sanam charn castle and Lumphini park, owning horses from Australia, which cost a great deal of money, while preaching his subjects to be austere and nationalistic. The most important factor for the coup was the king's introduction of senior scout to the nobility and the soldiers. The accomplice thought this interrupted the military orderliness and secretly consolidate the monarchial power. Nonetheless, this coup became the inspiration for the revolution in 1932.

King Vajiravudh could have been one of Thailand's very renowned artists in writing modern novel, short stories, play and even journal, if he hadn't been chosen to be the crown prince and the king. The private life of the king was the other issue for public controversy and rumors. He had lived as the bachelor for years, contradictory to his grand father and father who emphatically practiced the polygamy. The king liked to do his work, play cards and plays night and day with his favorites who were good looking young men, which led to suspicians that he might be gay. Finally he decided to get married, mostly to produce a heir of the throne as an essential factor for the stability of the throne. However he remained childless until two hours before his death his wife gave birth to a daughter. Thus his nephew became the new king Rama VII.

Amoung Vajiravudh's most notable accomplishments were the reform of the country's administration, increase of public education, the surname system as in western countires, the modern flag. However his most notable contribution was the focus on nationalism. King Vajiravudh could be praised as the father of Thai nationalism, which was later reproduced by Field Marshall Phibun Songkhram and Sarith Thanarath.