During the reign of King Tak Sin the Great, the King had a close aid-de-amp named "Phraya Pihai Dab Hak" who had studied the art of Muay Thai with many famous teachers and displayed his talent for the King.  As a result, he was chosen to become a soldier, and was later promoted to the position of Chao Muang (governor) with his name recorded in history.
In the Ratanakosin Period, Muay Thai was still a national art form, with competitions in annual national festivities.  Time-keeping was done by floating a pierced coconut shell.  When the coconut sank, a drum would be beaten to signal the end of a round.
In 1788, during the reign of King Rama I, two french brothers arrived in Thailand by boat, having defeated many boxers across the Indo-China Penninsula.  King Rama I consulted the Crown Prince, his brother, who offered to find boxers to fight against the Frenchmen.  Phraya Phra Klang would accept the challenge, settling the bet at 50 chang (4,000 bhat).  The Crown Prince chose a boxer named Muen Plan of the Royal Guards.  The match was held in the grounds of the Grand Palace.  Muen Plan wore full battle regalia--bare-chested, seeped in magic charms, cabalistic writing and oils to ensure invulnerability.  When the fight began, the large French fighter tried to attack, aiming for the neck and collar-bone.  Muen Plan defended himself with Muay Thai.  The other Frenchman, seeing his brother making no progress became frustrated, and pushed Muen Plan's back to stop him from backing away.  Members of the Royal Guards saw this break of boxing etiquette and proceeded to help Muen Plan tackle the two Frenchmen until they had to be carried back to the boat.  They set sail the next day, with no thought of ever challenging a Thai Boxer again.  
During the reign of King Rama V, Thai boxing matches were widely popular, boxing matches were held for the King's pleasure, ad skilled  boxers received titles from the King, for example Muen Muay Mee Chue from Chaiya, Muen Muay Man Mudh from Lopburi, Muen Cha-ngad Cherng Chok from Korat.  Also in this period boxing camps were established.  Members of the royal family sent out talent scouts to recruit potential boxers from up-country and arranged matches between camps.  Winners would receive money and valuable prizes.  This period could be called the Golden Age of Muay Thai.

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