Especially if you happen to be Bhumibol Adulyadej, more commonly known as Rama IX. The king of Thailand â€“ no Yul Brenner jokes, please â€“ has reigned since June 9, 1946, making him the world’s longest reigning current monarch and the worldâ€™s longest serving head of state. (The Thai monarchy has been in continuous existence since the founding of the Kingdom of SukothaiÂ in 1238.)Â Today is the king’s 85thÂ birthday and for the past ten days Iâ€™ve been greeted by billboard-sized photos of his majesty everywhere I go. ThisÂ littleÂ shrine outside my hotel was the mostÂ demureÂ example I could find.