The modern order of succession of Thai monarchs begins with king Si Inthrathit who established the Sukhothai Kingdom in 1238, which is considered to be the first contemporary Tai-ethnic kingdom; it was ruled by Phra Ruang dynasty. Composing of 8 dynasties: Phra Ruang, Uthong, Suphannaphum, Sukhothai, Prasat Thong, Ban Phlu Luang, Thonburi, and Chakri. With brief interruptions, 55 monarchs and 27 viceroys have ruled over four successive kingdoms, the current monarch being Vajiralongkorn (Rama X) of the Chakri dynasty.
The modern perception is that there has been four distinct eras of Thai history, namely: Sukhothai, Ayutthaya, Thonburi, and Rattanakosin. However, the compilations of historical narratives from the old capital (pongsawadan krung kao) and the historical narratives from the king in the temple compiled by Prince Tisavarakumara, the Prince Damrong Rajanubhab, along with the Chronicles of Northern Kingdom's Histories included the Pre-Sukhothai and Pre-Ayutthaya monarchs as well. This means that the Sukhothai-Si Satchanalai city-states and the Siam Confederation and their monarchs is a part of the historical cannon as well.
Prior to the establishment of Sukhothai, Siam was a group of petty kingdoms shifting zones of influences and mandalas through wars and political marriages. Because of this, there are kingdoms and polities which existence may overlap, hence the monarchs' reigns will also overlap or even reign two polities at once. An example are Sukhothai and Ayutthaya. Ayutthaya, in the modern sense, was established during the reign of Maha Thammaracha I of Sukhothai in 1351 in which king Uthong V & Ramathibodi I (same person with two regnal names) inherited all of the confederation's polities â uniting them, hence the reign of Ayutthaya's monarchs overlaps with 4 monarchs of Sukhothai. An example for a monarch reigning multiple polities is when king Phanom Thale Sri who reigned both the Siam Confederation and the Sukhothai-Si Satchanai city-states (together 5 different polities) at the same time in 1155, while these polities were ran separately and equal to one another unlike the vassalage system in which a state is subservient to another.
The traditional accounts of the list starts with king Phra Pathomsuriya Thephanarathai Suwannabophit as the first king of all of Siam in 757 CE. He was the first king to unite petty kingdoms under one monarch. His descendants are of the Guruwamsa/Pathomsuriyawong dynasty, which is also the ancestors to most of the reigning dynasty of Sukhothai and Ayutthaya. In which, according to the traditional accounts, king Uthong V, the first king of Ayutthaya is canonically considered to be the 27th monarch of Siam. The number of monarchs up to today would total to 101 monarchs.
All of the mentioned titles are now defunct due to the abolition of the peerage
Khun âÂ à ¸Âà ¸¸à ¸ â Originally meaning âÂÂlordâ or âÂÂchieftain,â Khun was a title used for local rulers or leaders of settlements. In later periods, is given to bureaucratic positions within government mostly to ministers, though a number of Shan states still retain this title for their rulers and kings. Originally a Tai word.
Phaya âÂ à ¸Âà ¸Âà ¸² (sometimes written à ¸Âà ¸£à ¸°à ¸¢à ¸² in later periods) â Originally meaning âÂÂlord.â In later periods, this title is given to people governing second-tier or lower-class cities. This title is now an equivalent to the title Marquess. Originally a Pali-Sanskrit word. This title was also used in numerous other Tai-ethnic kingdoms in the regions. The title is also adapted to a couple of higher titles such as Chao Phaya and Somdet Chao Phaya. Which is equivalent to Duke and Grand Duke in that order, though these title holders often do not hold fief / territory. Though when they do hold hand, it is tantamount to half the nation, such as the position of the prime minister of northern Siam, comes with the position of grand duke. The title is defunct. This title is also bestowed upon vassal kings and monarchs.
Pho Khun âÂ à ¸Âà ¹Âà ¸Âà ¸Âà ¸¸à ¸ â Originally meaning âÂÂlord father.â It reflects the paternal kingship ideology of the Sukhothai era, in which the king was regarded as a benevolent father to his subjects. The title is now defunct. Originally a Tai word.
Pu Khun âÂ à ¸Âà ¸¹à ¹Âà ¸Âà ¸¸à ¸ â Originally meaning âÂÂlord grandfather.â It is a term to used for deceased rulers. The title is now defunct. Originally a Tai word.
Pu Phaya âÂ à ¸Âà ¸¹à ¹Âà ¸Âà ¸Âà ¸² â Originally meaning âÂÂlord grandfather.â It is a term to used for deceased rulers. The title is now defunct. Originally a Tai + Pali-Sanskrit word.
Phrabat Kamrateng An Sri âÂ à ¸Âà ¸£à ¸°à ¸Âà ¸²à ¸Âà ¸Âà ¸±à ¸¡à ¸£à ¹Âà ¸Âà ¸Âà ¸Âà ¸±à ¸Âà ¸¨à ¸£à ¸µ â The monarch also adopted the Khmer prestige title Kamrateng An (Thai: à ¸Âà ¸¡à ¸ºà ¸£à ¹Âà ¸Âà ¸Âà ¸º à ¸Âà ¸Âà ¸º), meaning "our lord", as regnal title. The title is now defunct. Originally a Khmer word.
All of the mentioned titles are now defunct due to the abolishment of the peerage, except the title of Phra Chao and onwards
Muen âÂ à ¸«à ¸¡à ¸·à ¹Âà ¸ â Originally meaning "officer/baron." It is a title typically bestowed upon vassal king or a regional monarch and is not normally used on the kings of the Chao Phraya basin. The title is now defunct. In the chao phraya basin, it is bestowed upon officers within the central government.
Thao âÂ à ¸Âà ¹Âà ¸²à ¸§ â Originally meaning "lord/lady/sir/dame." It is a title typically bestowed upon a vassal king or a regional monarch and is not normally used on the kings of the Chao Phraya basin. The title is now defunct. In the chao phraya basin, it is bestowed upon officers within the central government and/or people who have achieved a great feat, akin to a knight or dame.
Khun Luang âÂ à ¸Âà ¸¸à ¸Âà ¸«à ¸¥à ¸§à ¸ â Originally meaning âÂÂroyal chief.â It is used for informal reference of the king. The title is now defunct.
Phra âÂ à ¸Âà ¸£à ¸° â Originally meaning âÂÂroyal or holy.â The title is now defunct. It was also used in the Sukhothai era.
Chao Luang âÂ à ¹Âà ¸Âà ¹Âà ¸²à ¸«à ¸¥à ¸§à ¸ â Originally meaning âÂÂroyal lord.â It is a title typically bestowed upon vassal king or a regional monarch and is not normally used on the kings of the Chao Phraya basin. The title is now defunct.
Chao Fa âÂ à ¹Âà ¸Âà ¹Âà ¸²à ¸Âà ¹Âà ¸² â Originally meaning âÂÂcelestial prince / celestial lord." usually used for viceroys and princes. It was used to refer to a number of Shan states still retain this title for their rulers and kings. The title is now defunct.
Krom Phrarachawang Baworn âÂ à ¸Âà ¸£à ¸¡à ¸Âà ¸£à ¸°à ¸£à ¸²à ¸Âà ¸§à ¸±à ¸Âà ¸Âà ¸§à ¸£ â Originally meaning âÂÂRoyal Front Palace Lord." The title is now defunct.
Somdet Phra Baworn Rat Chao âÂ à ¸ªà ¸¡à ¹Âà ¸Âà ¹Âà ¸Âà ¸Âà ¸£à ¸°à ¸Âà ¸§à ¸£à ¸£à ¸²à ¸Âà ¹Âà ¸Âà ¹Âà ¸² â Originally meaning âÂÂRoyal Highness the Exalted Vice-King." The title is now defunct.
Phra Chao âÂ à ¸Âà ¸£à ¸°à ¹Âà ¸Âà ¹Âà ¸² â Originally meaning âÂÂgod.â It is used for informal reference of the king. Though it is informal to refer to the chao phraya kingdom's king, it is nontheless the formal way to refer to the northern and other regional monarchs.
Chao âÂ à ¹Âà ¸Âà ¹Âà ¸² â Originally meaning âÂÂlord/prince/master." It is commonly used for loyalty and noblemen. The title is used to refer to a number of Shan states still retain this title for their rulers and kings.
Phrabat Somdet âÂ à ¸Âà ¸£à ¸°à ¸Âà ¸²à ¸Âà ¸ªà ¸¡à ¹Âà ¸Âà ¹Âà ¸ â Originally meaning "Most Exalted Majesty."
Somdet Phra âÂ à ¸ªà ¸¡à ¹Âà ¸Âà ¹Âà ¸Âà ¸Âà ¸£à ¸° â Originally meaning "Exalted Majesty."
Phrabat Somdet Phra âÂ à ¸Âà ¸£à ¸°à ¸Âà ¸²à ¸Âà ¸ªà ¸¡à ¹Âà ¸Âà ¹Âà ¸Âà ¸Âà ¸£à ¸° â Originally meaning "Most Exalted Royal Majesty."
Phrabat Somdet Phra Chao âÂ à ¸Âà ¸£à ¸°à ¸Âà ¸²à ¸Âà ¸ªà ¸¡à ¹Âà ¸Âà ¹Âà ¸Âà ¸Âà ¸£à ¸°à ¹Âà ¸Âà ¹Âà ¸² â Originally meaning "Most Exalted Majesty the Lord."
Phrabat Somdet Phra Poramenthara ... Chao Yu Hua âÂ à ¸Âà ¸£à ¸°à ¸Âà ¸²à ¸Âà ¸ªà ¸¡à ¹Âà ¸Âà ¹Âà ¸Âà ¸Âà ¸£à ¸°à ¸Âà ¸£à ¹Âà ¸¡à ¸Âà ¸Âà ¸£...à ¹Âà ¸Âà ¹Âà ¸²à ¸Âà ¸¢à ¸¹à ¹Âà ¸«à ¸±à ¸§ â Originally meaning âÂÂHis Most Exalted Majesty the Supreme Sovereign, the Lord Above Our Heads.âÂÂ
In the Sukhothai Kingdom, the monarch used the title Khun () or Phaya (), while Pho Khun/ Phaya () or Phoo Khun/ Phaya () were used to refer to deceased monarchs or senior relatives who were monarchs. The monarch also adopted the Khmer prestige title Kamrateng An (), meaning "our lord", as regnal title.
In the Ayutthaya Kingdom and afterward, thanandon, the system of Thai royal titles, determines the style of the monarch's full regnal name (which includes the title), consisting of two interconnected parts:
Western nations referred to the monarch as the "King of Siam" (), regardless of Thai titles, since the initiation of relations in the 16th century. Mongkut (Rama IV) was the first monarch to adopt the title when the name Siam was first used in an international treaty. When the kingdom's name was changed to Thailand, the monarch's Western title changed accordingly.
Due to intermarriages between Siamese polities, dynasties are usually branches or cadet branches of an already existing house. A dynasty may also arise from a minor member of a house through the right of conquest.
In the Siamese context, a dynasty includes all monarchs and their kinsmen who have ascended to the throne. This means that a dynasty encompasses individuals of the same bloodline, including brothers, uncles, and other relatives.
Within a dynasty, houses function as sub-units. Multiple houses can exist within a single dynasty. A king inherits his house from his father, regardless of whether the father was a reigning monarch; what matters is that the father was a son of a king or a vice-king. As a result, a dynasty may contain numerous housesâÂÂfor example, the Chakri Dynasty includes over a hundred cadet houses, divided into royal and viceroyal branches.
The concept of houses, by contrast, is a more recent construct used to describe subdivisions within a dynasty. Multiple houses can exist within the same dynasty, each representing a distinct patrilineal branch. A king is considered to belong to the house of his father, regardless of whether the father was a reigning monarch, as long as he was a son of a king or a vice-king.
Houses are passed from father to son. When brothers ascend the throne in succession, they belong to the same house if they do not have a son who later becomes king.
For example, Rama I, Rama II, and Rama III are considered part of the same house. Rama IV, however, is considered to be a part of a new house, as he was a brother of Rama III rather than his son. Rama V, Rama VI, and Rama VII belonged to Rama IVâÂÂs house; since neither Rama VI nor Rama VII had sons who became king, the house continued unchanged.
The throne later passed through Prince Mahidol, establishing another new house. His sons, Rama VIII and Rama IX, belonged to this same house, with Rama IX succeeding his brother.
In Siam, the relationship between the king and the viceroy (called the Uparaja) was based on shared rule but clear hierarchy. The king was the highest ruler, while the viceroy was usually a close relative chosen to help govern and serve as the likely successor, though this would often prove false due to other members of the family starting a succession war. The viceroy had real authority, controlling parts of the kingdom and managing government and military affairs when needed. However, all power officially came from the king, and the viceroy was expected to support and follow the monarchâÂÂs decisions. Because the viceroy had his own court and influence, this system sometimes led to rivalry or competition between the two.
The viceroys had their own palace and administration in the front palace.
The position continued for many centuries until King Chulalongkorn abolished it in the late 19th century to centralize power under the monarchy.
While the viceroy is not the king, throughout the history of Siam, there were moments where these viceroys were crowned "in equal power" as the monarch, like the coronation of Rama IV and Pinklao. In which king Pinklao was crowned using the title Phrabat Somdet Phra .... Chao Yu Hua in equal ranking to the first king. Thus, allowing the front palace to institute the first king's regalia and ornamentation within the front palace which had previously been forbidden.
The deputy viceroys had their own palace and administration in the rear palace. The deputy viceroy position was seldom bestowed. There had only been three bestowals in the last 700 years. This role is similar to the viceroys but are subservient to the king and the viceroy.
Co-kings were monarchs which had previously abdicated, but were invited back to power. Often they were brought back with the same amount of authority as the main king. Though this usually didn't last and often voluntarily relinquished power and even refused a third co-kingship. A famous example is when King Maha Thammarachathirat III was invited back into the position of king during King Borommaracha III<nowiki/>'s reign.
Tai peoples migrated into mainland Southeast Asia in the 8thâÂÂ10th centuries. In the years after, Northern Thai groups established mueang that evolved into larger states, such as Ngoenyang. However, it was not until the decline of the Khmer Empire in the 13th century that a Central Thai kingdom politically and culturally related to modern Thailand was first founded.
The Phra Ruang dynasty was the only royal lineage that ruled over the Sukhothai Kingdom, the first Central Thai state. Established by Si Inthrathit in 1238, who declared independence from the Khmer Empire, the dynasty laid the foundations for Thai society. Under Ram Khamhaeng the Great, the initial Thai script was invented and TheravÃÂda Buddhism was established as the state religion.
The dynasty is named after the Traiphum Phra Ruang, a Buddhist cosmology book written by Maha Thammaracha I. During his reign, the kingdom was invaded by Ayutthaya, a neighboring Thai state, becoming a tributary during the reign of Maha Thammaracha II.
In the Sukhothai Kingdom, the monarch ruled from the city of Sukhothai, while the heir presumptive would occasionally be named uparaja, or viceroy, and ruled in Si Satchanalai. In 1438, Ayutthaya annexed Sukhothai at the death of Maha Thammaracha IV when Borommarachathirat II of Ayutthaya named his son Prince Ramesuan uparaja. In Ayutthaya, the tradition would evolve into the Front Palace system.
The Ayutthaya Kingdom was a result of a unification between two states: the Kingdom of Suphannaphum (Suphanburi) and the Kingdom of Lavo. Though the Kingdom of Lavo was originally a Mon kingdom, the migration of the Tai peoples into the Chao Phraya basin replaced the original Mons, consequently becoming the governors of these regions. This resulted in the capital moving from Lavapura (Lopburi) and Suphannaphum (Suphanburi) to Ayodhya (Old Ayutthaya), a new capital. Later on, the Kingdom of Nakhon si Thammarat came under the influence of Ayutthaya after seceding from Sukhothai, and Sukhothai losing influence and coming under Ayutthayan influence.
This conflict would last long into the history of Ayutthaya Kingdom, where families from the four major regional kingdoms vie over the throne of the kingdom. These kingdoms are: Kingdom of Nakhon Si Thammarat, Kingdom of Sukhothai, Kingdom of Lavo, and Kingdom of Suphannaphum. The Kingdom of Sukhothai was integrated into the Kingdom of Ayutthaya along with its noble families.
As previously mentioned, the kingdom of Ayutthaya was the result of the unification between two federations: Lavo and Suphannaphum. The ruling dynasty of Lavo gave rise to the Uthong Dynasty, in which the Suphannaphum dynasty came from the Suphannaphum federation. This federation held significant influence within the kingdom leading them to take control of the throne in 1310.