The Thai crown prince was invited by the country’s parliament to become their new king following a Buddhist rite marking 50 days since the king's death.
Paying respects to his late father, Thailand's new king knelt in front a picture, as servants prostrated in the background.
Some likened it as a scene reminiscent of classic musical The King and I, also set in Thailand (formerly Siam).
The King And I: Thailand's Crown Prince ascends to take the crown 50 days after his father's death as flunkies lie on the floor around him…— Let's travel! (@wanderrlove) December 1, 2016
Thailand has been without a monarch since King Bhumibol died on Oct. 13. The monarchy has been run by 96-year-old regent Prem after the prince asked to delay the succession in order to grieve.
Prince Vajiralongkorn will be known as King Maha Vajiralongkorn Bodindradebayavarangkun, Rama X, or the 10th king of Thailand's Chakri Dynasty according to a statement released by parliament's public relations department.
King Maha Vajiralongkorn has spent much of his adult life abroad and has a home in Germany. Over the past few years, however, the he had taken on more of his father's ceremonial duties while the late king received medical treatment.
The new king's personal life and suitability as monarch has been the subject of private speculation by Thais and overseas observers beyond the reach of the law.
The new King Maha Vajiralongkorn has yet to command the kind of adoration that his father received from Thais and he has kept a much lower profile throughout most of his adult life.
The king, however, like his father before him, is shielded from public criticism by Thailand's lese majeste laws, which carry a penalty of up to 15 years in prison.
The law has curtailed public discussion about the succession, the future of the monarchy or criticism about the crown prince, who has led a scandal-plagued life.