Phrabat Somdet Phra Chairachathirat () (Reigned 1534-1546) was King of Ayutthaya (Siam). His reign was remarked of the first war between Siam and Burma and the influx of Portuguese traders and warfare technology.

Uparaja

Prince Chairachathirat was a son of King Ramathibodi II. In 1533, following the death of Borommaracha IV who was his brother, Prince Chairachathirat was appointed the Uparaja of Pitsanulok as his newphew Prince Ratsadathirat (who was then Borommaracha IV's son) succeeded the Ayutthayan throne.

Government authority under five-year-old Ratsadathirat was proved to be weak. In 1534, only five months after his newphew's ascension, Chairacha marched to Ayutthaya to staged a coup, killed his newphew, and took the throne of Ayutthaya.

King of Ayutthaya

Wars with Burma

In 1539, Tabinshweti of Pegu led Burmese armies into Siam and took the Siamese fort of Chiang Kran. Chairacha then led the Siamese armies to recapture Chiang Kran. The Siamese was able to retake the fort - thanks to Portuguese arquebusiers. The Chiang Kran campaign was known as the first of the conflicts between Siam and Burma that lasted for about another two centuries.

Chairacha then granted the lands near Ayutthaya to establish Portuguese quarters - a place for the Portuguese to reside and trade. He also permitted the constructions of the monasteries and the entrance of Catholic missionaries.

Invasion of Lanna

In 1545, King Kaew Kesa of Lanna was overthrown. Chairacha took this opportunity to invade Lanna, where he was greeted peacefully by Queen Chiraprapa - daughter of King Kaew Kesa. However, Tabenshweti was able to impose the Burmese influence over Lanna kingdom under Queen Chiraprapa. Chairacha, fearing that Lanna would became the base for the Burmese to invade Siam, led an expedition in 1546 to get rid off the Burmese influence. He sacked Lampang and Lampoon and he ordered Tianracha the Uparaja to invade Chiang Mai. Queen Chiraprapa then sued for peace and put her kingdom under the tributary of Ayutthaya, for the first time.

He ordered a shortcut to be made through the bends of the Chao Phraya river in the area of current-day Bangkok. This is now the main river course.

Sukhothai nobles

Chairacha appointed his brother Prince Tianracha (later Maha Chakkrapat) as the Uparaja but didn't granted him the title of King of Sukhothai as Chairacha tried to unite the two kingdoms by reducing the power of Sukhothai nobles. He also called the Sukhothai nobles to Ayutthaya to move them from their base at Pitsanulok and made Ayutthaya the sole center of authority.

Mysterious Death

The sources conflicts about the nature of Chairacha's death. The Portuguese chronicles of Fernão Mendes Pinto said he was poisoned by his concubine Sri Sudachan from Uthong clan in 1546. This can be inferred from the later power struggles involving Sri Sudachan and her lover Khun Vorawongsathirat. However, some Siamese chronicles said Chairacha died of an illness after going to war.

Category:1546 deathsCategory:Thai monarchsCategory:Rulers of Ayutthaya
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