BANGKOK - An officer in the Thai military, His Royal Highness Crown Prince Maha Vajiralongkorn has trained with the Australian, British and the United States armed services.
His Royal Highness Crown Prince Maha Vajiralongkorn, 64, had been heir apparent to the Thai throne for more than 43 years.
The Prince was born on July 28, 1952, as the second child and only son of Their Majesties, at Dusit Palace's Ambara Villa in Bangkok.
In December 1972, when Prince Vajiralongkorn was 20, His Majesty King Bhumibol Adulyadej bestowed him with the title of Crown Prince.
The full title bestowed was "Somdech Phra Boromma-orasadhiraj Chao Fa Maha Vajiralongkorn Sayam Makut Rajakuman," which translates as "Prince Maha Vajiralongkorn, the Royal Son and Crown Prince of Siam."
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The bestowing ceremony was held at the Ananta Samakhom Throne Hall in line with the 1924 Palace Law on Succession to the Throne.
After the ceremony, the Crown Prince took an oath of allegiance at the Emerald Buddha Temple in the Grand Palace compound.
While taking the title, the Prince announced that he would be loyal to the country and sincere to the people.
"I will perform my duties to the best of my intelligence and ability, and also with devotion, for the peace and prosperity of Thailand," he said.
BBC reporter David Lomax asked the Prince about the pressure he would undergo in his new title.
"In every life I believe there is pressure, stress and problem. It is the same for everybody. There are pros and cons, advantages and disadvantages. I am not special," the Prince answered.
The interview appeared in a BBC documentary entitled "Soul of a Nation: The Royal Family of Thailand" broadcast in 1980.
Prince Vajiralongkorn completed his primary education at Chitralada School in Bangkok, and later at private colleges in the United Kingdom and Australia.
He graduated from the Royal Military College of Duntroon in Canberra and the University of New South Wales in Australia, majoring in military studies.
He also has a bachelor's degree in law from Sukhothai Thammathirat Open University.
As an officer in the Thai military, he trained with the Australian, British and the United States armed services, studying special forces demolition, unconventional warfare tactics and advanced navigation training.
He is also a qualified pilot of military helicopter and jet-fighter aircraft.
The Prince also holds the titles of Army General, Navy Admiral and Air Chief Marshall of the Air Force.
The Crown Prince first joined the military in January 1975 as an officer with the Royal Thai Army's Intelligence Department.
In October 1978, he was appointed as deputy commander of the King's Royal Guards Battalion of the First Infantry Regiment and then promoted to become the battalion commander in November 1980.
In February 1984, he became commander of the Royal Guards Regiment and in January 1992 chief commander of the Royal Guards Command, which is part of the Armed Forces Supreme Command.
In the 1970s, as a young military officer, the Prince took active part in military operations against communist insurgency in the North and Northeast, many areas of which were under the influence of the Communist Party of Thailand at the time.
He also led counter-insurgency campaigns against the communist forces.
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As many as 21 Crown Prince Hospitals, called Somdej Phra Yuparaj in Thai, are built under his royal patronage in several rural areas of the country and the Prince serves as honorary chairman of the foundation that runs these hospitals.
In recent years, the Prince has regularly represented Their Majesties King Bhumibol and Queen Sirikit in several important state and royal functions.
Last year, the Crown Prince initiated two nationwide cycling events "Bike for Mom" and "Bike for Dad," in August and December respectively, in honour of Their Majesties the King and Queen.
The Crown Prince has two daughters, Her Royal Highness Princess Bajra Kitiyabha and Her Royal Highness Princess Sirivannavari Nariratana, and a son, His Royal Highness Prince Dipangkorn Rasmijoti.