King Thammaracha, now reigned at Ayutthaya, appointed his son Prince Naresuan as the "Uparaja" of Phitsanulok in 1570. In 1584, Prince Naresuan ordered the evacuation of all cities in the Sukhothai region including Phitsanulok down south in preparations against Burmese invasions. Phitsanulok was abandoned until it was later restored in 1593 not as a "Uparaja" seat but as a "Muang Ek" or first-level city held by a governor, becoming the center of Siamese administrations in northern regions. The governors of Phitsanulok held the title ""Chao Phraya" Surasi". After the Second Fall of Ayutthaya in 1767, Phitsanulok came under the rule of Chao Phra Fang, a monk who declared himself a local lord based on the town of Fang (modern Uttaradit). King Taksin of Thonburi sent forces to capture Phitsanulok in 1768 and appointed Boonma (later Prince Maha Sura Singhanat) as "Chao Phraya" Surasi the governor of Phitsanulok.