The earliest historical records relating to what is now Phitsanulok Province indicates that at a time prior to or during the 11th century, the present-day city of Phitsanulok was but a small strategic Khmer outpost known as Song Khwae. During the next century, in 1188, Nakhon Thai, located near the center of the present Phitsanulok Province, was established as the capital city of the Singhanavati Kingdom, an early city-state of Thailand. Later, during Thailand's Sukhothai Period, the city of Phitsanulok emerged as a major city in the east of the Sukhothai Kingdom, and the great temples of Wat Chula Manee, Wat Aranyik and Wat Chedi Yod Thong were constructed. In 1357, the renowned Wat Phra Sri Rattana Mahathat was erected, and the Ayutthaya Period witnessed the construction of several of the province's other chief temples. Phitsanulok served for 25 years as the capital city of the Ayutthaya Kingdom. In 1555,