Guo Jia vs Ziyad ibn Abihi

Guo Jia presented the 'Ten Advantages and Ten Disadvantages' analysis, arguing that Cao Cao had the strategic edge over Yuan Shao. He also predicted Yuan Shao's indecisiveness and the eventual betrayal of his subordinates, contributing to Cao Cao's victory.

Guo Jia advocated for a swift campaign against the Wuhuan tribes in the north, despite the risks of a long march. The campaign succeeded, eliminating a threat to Cao Cao's rear and securing his northern frontier.

Guo Jia fell ill and died at the age of 37 during the return from the Wuhuan campaign. His early death deprived Cao Cao of a key strategist, and Cao Cao later lamented that Guo Jia's absence contributed to the defeat at Red Cliffs.

Caliph Muawiyah I appointed Ziyad ibn Abihi as governor of Basra, a major garrison city in Iraq. Ziyad's administration was marked by strict discipline and effective governance, which he used to suppress dissent and consolidate Umayyad control.

Ziyad ibn Abihi launched a brutal campaign against the Kharijite rebels in Iraq. He employed spies, informants, and military force to crush the rebellion, executing thousands and establishing a reign of terror that effectively ended Kharijite resistance in the region.

Ziyad ibn Abihi was given unified control over Basra, Kufa, and the eastern provinces of the Umayyad Caliphate. This consolidation of power made him one of the most influential governors, responsible for administering a vast territory from Iraq to Khorasan.