1487 - Maharaja Tilok dies.
1488 - King Trailok dies in Phitsanulok and is succeeded by his son, Boromaraja III, who had been his deputy in Ayutthaya for 25 years. As Boromaraja III has his personal base in Ayutthaya, the city’s traditional function as capital is restored. Boromaraja’s younger brother, Prince Jutta, becomes governor of Phitsanulok.
1491 - Boromaraja III dies and is succeeded by Prince Jutta who takes the title Rama Tibodi II.
1507 - A civil war breaks out in Chiang Mai and the local ruler, Maharaja Yai, is deposed and succeeded by his son Maharaja Ratna. The following years, until 1515, there are a number of clashes between Siam (Ayutthaya) and Lannatai (Chiang Mai) armies which however don’t change the power balance between the two kingdoms.
1511 - Duarte Fernandez, a Portuguese, lands in Siam and negotiates a treaty with King Rama Tibodi II to permit Portuguese to reside and carry on trade in Ayutthaya.
1515 - Sukhothai is invaded by the ruler of Laos, then a principality covering roughly the area of present-day Laos.
1529 - King Rama Tibodi II dies after a reign of 38 years. His son, Prince Atityawong, succeeds the throne as King Boromaraja IV.
1533 - King Boromaraja IV dies early of smallpox, leaving as successor to the throne his 4 year old son, Prince Ratsadatiratkumar. After a reign of just five months in which his ministers rule in his behalf, Prince Prajai (a half-brother of the former King Boromaraja IV, sizes the throne in 1534 after having the child king murdered. After the 15 year old King Tonglan in 1388, Prince Ratsadatiratkumar is the second child king to ascend to the throne, and like the former he is disposed and killed by an older relative. In the next decades and the next centuries, a similar fate will befall practically all underage ascendents to the throne. Furthermore, palace revolts and usurpations of the throne become a fairly normal feature for the remaining centuries of the Ayutthaya period in Thai history. While the Ratsadatiratkumar/Prajai case doesn’t interrupt the initial dynasty of Ayutthaya (Prajai like Ratsadatiratkumar being a close relative of the former king) palace revolts of the following centuries do interrupt dynastic lines and none of the subsequent three dynasties makes it to 80 years in power.
1545 - King Prajai intervenes in the affairs of Chiang Mai leading to a short war between Burma and Ayutthaya. The Siamese ultimately retreat after destroying Lamphun, then in Burmese territory. The Lannatai Kingdom of Chiang Mai elects to ally itself with Burma and will be on the side of the Burmese more often than the side of Siam for most of the time in the next decades and centuries.
1546 - King Prajai returns to Ayutthaya and dies there. The King is said to have been poisoned by his wife, Tao Sri Sudachan. King Prajai is first succeeded by his 11-year old son Kaeofa. While Prince Tienraja acts as the Regent in behalf of King Kaeofa, the dowager queen Tao Sri Sudachan wields considerable influence and is able to widen her power base. After she succeeds in pushing Prince Tienraja to become a monk, she rules pretty unchallenged. In her private life she chooses a minor palace official as her lover.
