Although the official narrative based on Sai On's Chūzan Seifu is widely circulated, it is full of contradictions with contemporary sources.
Shō Hashi conquered Hokuzan (Sanhoku) in 1416 and Nanzan (Sannan) in 1429, unified Okinawa successfully.
[10] King Shō Toku died in 1469, and his offspring was killed in a coup d'état by Kanemaru, who took over the royal name to disguise the coup d'état as a normal succession and thereby became the founder of the second Shō Dynasty.It was Sai On who first claimed that Chūzan annihilated Hokuzan in 1416 and Nanzan in 1429.
Having access to Chinese records, Sai On naïvely inferred that the two kings were removed immediately after the last missions.
According to the Chūzan Seikan, Shō Hashi succeeded his father Shishō as Aji (local ruler) of Sashiki in 1402.
In 1423, Shō Hashi reported the unification to the Ming emperor, and Shishō was posthumously appointed as King of Chūzan.
Similarly, Crown Prince Shō Hashi reportedly succeeded his late father Shishō as King of Chūzan in 1425.
Contemporary sources left by two separate groups of Korean drifters show no trace of the alleged large-scale fire.
[13] Sai On's modifications to the traditional Okinawan narrative were based on Chinese sources, where Shō Taikyū reported the alleged struggle to the Ming emperor in 1454.
[13] According to the Okinawan narratives, the last King Shō Toku was 29 years old when he died in 1469, leaving an infant son.
Another Korean source named the Haedong Jegukgi records a statement by the Zen monk Jitan Seidō, who visited Korea as an envoy of the King of Ryūkyū in 1471.
[13] In light of contemporary sources, it is clear that the Okinawan narratives claimed Shō Toku and his child(ren) to be much younger than they really were.