King Bhumibol Adulyadej’s Birthday / National Day / Father’s Day in Thailand Date in the current year: December 5, 2024

Bhumibol Adulyadej was born on December 12, 1927 to Prince Mahidol Adulyadej, the younger brother of King Rama VII, and his commoner wife Sangwan (later Princes Srinagarindra). He was born in Cambridge, Massachusetts because his father was studying public health at Harvard at the time. The family returned to Thailand the next year, and a year later, the future king’s father died of kidney failure.

Bhumibol briefly attended a school in Bangkok, but the family left Thailand to Switzerland in 1933. He enrolled at a co-ed private school in Lausanne and, upon receiving his high school diploma, entered the University of Lausanne to study sciences. While Bhumibol was living in Switzerland, his uncle abdicated and was succeeded by Bhumibol’s elder brother Ananda Mahidol, who was only nine years old. The country was in fact ruled by a regency council because Sangwan opted to remain in Switzerland with her family.

The family returned to Thailand after the end of World War II. On June 9, 1946, the 20-year-old King Ananda Mahidol was shot with a gun under circumstances that remain unclear to this day. Bhumibol succeeded his brother and ascended to the throne as King Rama IX, but returned to Switzerland to continue his studies, switching his major from science and technology to law and political science.

Bhumibol was officially crowned on May 5, 1950. He was the first King of Thailand to ascend the throne under constitutional monarchy. Rama IX ruled the country for seven decades; at the time of his death, he was the world’s longest-reigning head of state, the longest-reigning monarch in the history of Thailand and the longest-reigning monarch having reigned only as an adult.

His reign was marked by several military coups that resulted in military rule. During these periods of military dictatorship, Bhumibol had no real power and was just a ceremonial figure. In 1992, he helped solve a major political crisis and made Thailand return to a democratic system.

King Rama IX enjoyed immense popularity and was well-respected by his subjects. In his private life, he was an accomplished musician, painter, photographer, author, translator, sailor and sailboat designer, radio amateur, and a holder of several patents.

The king died on October 13, 2016 and was succeeded by his only son, Crown Prince Maha Vajiralongkorn. Some people thought that the country’s National Day, coinciding with the King’s birthday, would be moved to the birthday of the new monarch, but this didn’t happen. While King Vajiralongkorn’s birthday was indeed declared as a public holiday, it is Bhumibol Adulyadej’s birthday that still serves as the national day of Thailand. Moreover, it also serves as National Father’s Day.