Didao

Didao is the setting for a reversal in Jiang Wei’s northern campaign: after defeating Wei troops at the River Tao, he advances on the city, only to be caught by Deng Ai’s ambush and driven back toward Hanzhong. The episode presents Didao as the next strategic objective in a campaign whose initial success does not guarantee a lasting gain.

From the River Tao to Didao

Jiang Wei’s forces first defeat the Wei army led by Wang Jing, which had expected to trap the Shu troops with their backs to the River Tao. The victory gives Jiang Wei an opening to continue toward Didao. Zhang Yi urges him to treat the River Tao success as sufficient, but Jiang Wei presses ahead, turning a defensive triumph into a new attack.

The Ambush and Retreat

Chen Tai moves Wei forces to defend Didao. Jiang Wei is drawn into an assault that becomes an ambush set by Deng Ai, an experienced Wei general. The Shu army is defeated, and Jiang Wei withdraws to Hanzhong. The episode closes not with the capture of Didao but with Jiang Wei already planning another invasion of Wei, leaving the city as the point where momentum turns into setback.

Strategic Significance

Didao marks the limits of the River Tao victory in this account. Jiang Wei’s advance extends the campaign beyond its first success, while the Wei response converts the city into a defensive objective and an opportunity to counterattack. The contrast between the two stages—victory at the river, defeat before Didao—shows how quickly a battlefield advantage can be undone when an advance meets a prepared opponent.