This paper examines Emperor Qianlong's identity construction and historical analysis concerning the Mandala System, guided by a case study on social acquisition mechanisms. The author argues that Emperor Qianlong did not recognize or share the identity setting regarding China's role in the Mandala System, a unilateral policy design and understanding of Thailand's monarchs. The rewriting of imperial letters from China led to the misconception that the Chinese emperor internalized the country's role identity. This resulted in Thailand's monarchs following the teachings of Kautylia's Arthasasthra and engaging in political exchanges with China. However, the diplomacy between Thailand and the Ming dynasty during the Imjin War is not a convincing case to prove that the Mandala System influenced Thailand's diplomacy with the Chinese dynasty. The author suggests that theoretical thinking regarding diplomatic strategy can help provide an interpretation framework that integrates the subjectivity of China and Southeast Asian Kingdoms before the early 19th century.