In the year 1563 (B.E. 2106), King Bayinnaung of Hongsawadi mobilized his grand army to invade the Kingdom of Ayutthaya, successfully seizing the northern provinces, with 'Phitsanulok' serving as the capital. At that time, 'Somdet Phra Maha Thammaracha' (the ruler of Phitsanulok and father of King Naresuan the Great, or Phra Ong Dam) was compelled to submit to King Bayinnaung to protect the lives of his subjects from peril. Furthermore, he was forced to join the Burmese military procession in their assault on Ayutthaya.