After unifying China, Shi Huangdi divided the country into military districts to ensure efficient governance and maintain control over the vast territory. This administrative division allowed for better management of resources, troop deployment, and enforcement of laws. By centralizing authority within these districts, Shi Huangdi aimed to suppress potential rebellions and consolidate his power, facilitating the establishment of a strong, centralized state. This strategy also helped in the integration of diverse cultures and regions under a unified Chinese identity.
Mesopotmia ;was about independence while Egypt was more about unifing
Ideology
There isn't a dynasty that are the strongest dynasty of China. Some times the dynasty is stronger, sometimes the dynasty s weaker, so it depends on the time you're talking about. For example, when the Shi Huang Di just unifing China, the Qin dynasty was very strong, but when his son ruled China, the Qin dynasty became really weak.
Ieyasu defeated his rivals at the battle of Sekigahara in 1600. The victory earned him the loyalty of daimyo throughout Japan. He later became the sole shogun and moved the capital, unifing Japan.