War of the Eight Princes
Emperor Wu immediately sought to avoid what he saw as Cao Wei's fatal weakness—lack of power among the imperial princes. In 265, immediately after taking the throne, he made princes of many of his uncles, cousins, brothers, and sons, each with independent military commands and full authority within their principalities. This system, while it would be scaled back after the War of the Eight Princes and the loss of northern China, would remain in place as a Jin institution for the duration of the dynasty's existence, and would be adopted by the succeeding Southern dynasties as well.