Jēṣṭhādhirāj

His Majesty King Chetthathiraj (c. 1613 - 1629, full Thai title: สมเด็จพระเชษฐาธิราช; RTGS: "Somdet Phra Chetthathirat") was the eldest son of King Droṇdharm and older brother of King Ādiŧyavoṇś, all three of the House of Sukhōday. In childhood he was known as Chetthākumār (พระเชษฐากุมาร; "Phra Chetthakuman") meaning 'Chettha the Child' or simply Chettha. He reigned for a period of eight months from 1628-1629.

When his father King Droṇdharm died there was a scramble for the crown between Prince Jēṣṭhā and his younger brother Prince Śrīśilҏ (พระศรีศิลป์; "Phra Sisin"). On Jēṣṭhā's side were the ạkñās Śrīvạravoṇś and Śrīsēnābhimukh (n.b. Ạkñā (ออกญา; "Okya") is a title above Khun) who were influential enough to capture Śrīśilҏ and have him executed. After doing just this, they then informed Jēṣṭhā of the deed and he ascended the throne as His Majesty King Jēṣṭhādhirāj or His Majesty King Pạromarājādhirāj II (สมเด็จพระบรมราชาธิราชที่ ๒; "Somdet Phra Borommarachathirat thi Song"); he was fifteen years old at the time. Ạkñā Śrīvạravoṇś was then also promoted to the title of Cēābrayā Kalāhōm Suriyavoṇś (เจ้าพระยากลาโหมสุริยวงศ์; "Chao Phraya Kalahom Suriyawong").

After reigning for eight months he became suspicious of Kalāhōm Suriyavoṇś' ambition to take the crown for himself and plotted out a way to get rid of him. This was discovered by Kalāhōm Suriyavoṇś before it could be realised however, and the latter thus launched an attack on the residential palace with King Jēṣṭhādhirāj fleeing rather than countering the attack. Kalāhōm Suriyavoṇś dispatched two figures, the brayās Tējō (เดโช; "Decho") and Dāynaṃ (ท้ายน้ำ; "Thainam") to follow suit immediately and capture Jēṣṭhādhirāj in the Mōknạy Forests (ป่าโมกน้อย; "Pa Mok Noi"), where Jēṣṭhādhirāj was subsequently caught and killed.

"source: Thai Wikipedia"