Bird's nest was the nest of swiftlets living in Sumatra, Kalimantan, Siam, and Malaysia. The swallows chewed seaweed in their mouths, turning it into a gelatinous substance. It was brought to China by ships arriving from Siam during the Qing dynasty, though even more came from Southeast Asia and Japan.
The Qing–Burma War was one of Qianlong's "Ten Great Campaigns." After the war ended, the Qing court sent envoys to confer a title upon the king of Burma, formally establishing a suzerain-vassal relationship.
Yet Siam stopped paying tribute. Compared with Burma, which had only reluctantly become a vassal of the Qing Empire after more than ten years of war with the Qing dynasty, Taksin of Guangdong submitted a memorial to the Qing court from the very beginning of establishing his regime. He hoped to replace the king of Ayutthaya and be invested by the Qing emperor as king of Siam.
However, Qianlong believed that he had acquired power illegitimately and refused to recognize him, sending back a harshly worded rebuke. Three years later, during the Qing–Burma War, Taksin escorted a batch of Burmese captives as tribute and again requested investiture. After many twists and turns, Taksin was finally recognized by the Qing court as king of Siam, and the Thonburi Kingdom was once again incorporated into the Central Plains' suzerain-vassal system.
The tributary system was a hierarchical, networked political order centered on the dynasties of the Central Plains. By investing rulers beyond the Central Plains and establishing suzerain-vassal relations, the Central Plains dynasties formed the concept of All Under Heaven, a universal sovereign over the world where "under all heaven, there is no land that is not the king's."
On this foundation, Southeast Asia also formed a Mandala System. Northeast Asia belonged to the Chinese-character cultural sphere, while Southeast Asia