Royal Standard of Thailand

The Royal Standard of Thailand (Thai: ธงมหาราช Thong Maharat) is the official flag of the King of Thailand. The standard was adopted in its present form in 1910 under King Vajiravudh (Rama VI), superseding the first Royal Standard created by King Mongkut in 1855. In 1979, the designs were codified by law; specifically in Article 2 of the Flag Act of 1979 (พระราชบัญญัติธง พ.ศ. ๒๕๒๒), which also regulated Thailand's other flags. The standard is currently used by King Maha Vajiralongkorn, also known as Rama X, since 2016.

The Royal Standard consists of a bright yellow square with a red Royal Garuda at the center. The mythical Hindu and Buddhist beast: the Garuda is the national emblem of Thailand and the official symbol or 'arms' of the King of Thailand. The Garuda has been the symbol of the monarchy since the time of the Kingdom of Ayutthaya. Readopted in 1910, King Vajiravudh decided to replace all of the Royal Standards (for the King and other members of the Royal Family) to feature the Garuda.

The standards are usually hoisted at the King's palace of residence, sea or land vehicles and as an emblem on the side of the royal aircraft. The standard is also used on ceremonial occasions and official business by the King. The use of these standards are reserved exclusively to the monarchy and are not commonly seen. Unlike the King's personal flag which are commonly seen all over Thailand, usually flying alongside the National flag.

The Law also adopted flags for other members of the Royal Family as well as the Regent of Thailand.

King Mongkut (Rama IV) felt the need to create a Royal standard to distinguish his royal barge from other vessels during his many travels around the Kingdom and to fly above the Grand Palace in Bangkok when he is in residence. In 1855 a Royal Standard was created called the 'Thong Chom Klao' (ธงจอมเกล้า).

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Wikipedia