Prince Prajadhipok Sakdidej born in B.E.2436 (the 76th son of King Rama V and Queen Sri Bajarindra
(the youngest of nine children born to the couple)
During King Rama VI reign, the king announced to give the throne to his son if born from Princess Suvadhana. If not, the throne would pass to his brother Prince Prajadhipok (King Rama VI had no son -only one daughter).
After graduation from the Woolwich Military Academy in B.E. 2456, Prince Prajadhipok was commissioned in the British Army and the Royal Siamese Army.
Due to the First World War (B.E.2457- 2461) and the declaration of Siamese neutrality, King Rama VI ordered Prince Prajadhipok to resign his British commission and return to Siam immediately (became a high-ranking military official in Siam as Krom Luang Sukothai)
In B.E. 2461, Prince Prajadhipok married his cousin (Princess Rambhai Barni) in attendance of King Rama
VI at the Varopad Piman Mansion, Bang Pa-In Summer Palace.
The first official wedding for the Royal Family because the King Rama VI had passed the wedding law and no official weddings before (only a male royal taking a female as his consort (companion) and minor wives).
After the wedding law was passed, the practice of "marriage" became a Western marriage.