Why did traditional Chinese historians describe Taizong as a key founder of the Tang dynasty?

Traditional Chinese historians often portrayed Taizong as a primary founder of the Tang dynasty by emphasizing his role as the driving force behind the initial uprising against the Sui dynasty in 617. While historical evidence suggests his actual contribution to the rebellion's inception was minor compared to his father, the Gaozu emperor, Taizong actively encouraged the creation of myths surrounding his leadership.12

These narratives were further solidified by court historians who produced idealized accounts, such as the Zhenguan zhengyao, which depicted his reign as a utopian model of governance. By framing Taizong as a decisive, Confucian-minded ruler who governed through talented ministers, these records elevated his status to that of a foundational figure. In reality, however, most of the dynasty's essential institutions, legal codes, and government structures were established by his father, Gaozu; Taizong’s primary achievement was the effective implementation and restoration of these systems following years of civil war.12