การเมืองไทยในลุ่มน้ำเจ้าพระยาตอนล่างจากสมัยเมืองคู่สู่สมัยราชอาณาจักร : กรณีศึกษาพัฒนาการของวังอยุธยาและต้นกรุงเทพฯ / นพดล ปาละประเสริฐ = Thai politics in the lower Chao Phraya basin from the period of twin cities to the period of kingkoms : a case study of the development of Ayutthaya and early Bangkok palaces / Naphadol Paraprasert
This study finds that before becoming a kingdom the cities in the Chao Phraya River Basin were grouped as independent towns-twin cities such as Suphanburi (Suphanaphum)-Phraek Si Racha in the Mae Klong-Thachin basin and Lopburi (Lawo)-Ayutthaya (Ayothaya) in the Lopburi-Pasak basin. In this period, the administrative center of the town was the wang within a wiang. The wang was the residence and work place of the ruler in small towns (wiang), such as King Ramathibodi I's wiang lek. Later King Intharacha united both regions, reformed the administration and bureaucratized muang luk luang by appointing royal sons as somdet no phra phuttha chao and phra maha uparat, sending royalty to govern Phitsanulok, a first class province. As a result, Ayutthaya became the governing center, with a large and complex Royal Palace. The Palace was divided into three sections: outer, central, and inner, with Wat Phra Si Sanphet included in the palace area. King Chairacha cancelled the muang luk luang system, a measure that became fully effective in King Naresuan's time, when many khunnang governed provinces and princes remained in Ayutthaya, forming a kind of centralization. The wang na (Front Palace) and wang lang (Rear Palace) thus came into being. King Prasatthong tried to diminish the khunnang's authority and strengthened the Royal Palace by building throne halls and expanding the palace walls. His son King Narai avoided staying in Ayutthaya, preferring to set up his court and power base at Lopburi. King Phetracha moved the court back to Ayutthaya, using the inner court at the back of the Royal Palace as the front, in order to prevent attack. He also appointed the Front Palace and Rear Palace princes as krom phra racha wang bowon sathanmongkhon and krom phra racha wang bowon sathanphimuk respectively. Royal political power was thus concentrated in the capital, especially with the phra maha uparat as a large krom holder, with enough resources to challenge the king's power. King Borommakot appointed his sons to small krom, instead of appointing a phra maha uparat. At the end of his reign he appointed Kromkhun Phonphinit (later King Uthumphon) as uparat. There were no more phra maha uparat until the reign of King Rama I, who re-established the Front Palace, Rear Palace, and smaller krom, to be used as manpower sources in war, rather than as the king's own power base.
