Constitution Day in Thailand is observed annually on December 10. It commemorates the adoption of the country's first permanent constitution in 1932, which marked the transition from absolute monarchy to constitutional monarchy.

When is Constitution Day?

Constitution Day is observed every year on December 10.

The following is the list of Constitution Day from 2020 to 2049.

The History of Constitution Day?

From its founding in 1782 until 1932, Siam (now Thailand) was ruled by absolute monarchs from the Chakri Dynasty. The king held complete control over the legislative, executive, and judicial branches of government.

On June 24, 1932, a group of military and civilian officials known as the Khana Ratsadon (People's Party) staged a bloodless coup. They demanded an end to absolute monarchy and the creation of a constitutional government.

King Prajadhipok (Rama VII) agreed to the demands and initially signed a temporary constitution.

On December 10, 1932, King Prajadhipok signed the first permanent constitution of Siam. This document established the legal basis for a constitutional monarchy, an elected parliament, and the rule of law. It represented a dramatic and peaceful transformation of the Thai political system.

In 1933, the government designated December 10 as "Constitution Day" (Wan Rattha Thammanun) to honor the historic event. It has been observed annually ever since, making it one of the longest-standing civic holidays in Thailand.