Is “Taigong's military strategies and founding Qi” true?
attested in history
Both the Records of the Grand Historian, Hereditary House of Qi Taigong, and the Book of Documents, Gu Ming, record that he was enfeoffed with Qi for his merits, established the state of Qi, and left behind military thought that was passed down; this is indeed recorded in official history.
Jiang Ziya
In official history, he is the founding minister of Qi and the ancestor of military strategists; in novels, he is portrayed as a Taoist master who descends the mountain to oversee the canonization of gods.