Constantine the Great vs Qin Shi Huang

Constantine defeated his rival Maxentius at the Milvian Bridge near Rome. According to tradition, Constantine saw a vision of a cross in the sky with the words 'In this sign, conquer.' The victory made Constantine the sole ruler of the Western Roman Empire and led to his conversion to Christianity.

Constantine and his co-emperor Licinius issued the Edict of Milan, granting religious toleration to all religions in the Roman Empire, including Christianity. The edict ended the persecution of Christians, restored confiscated church property, and established Christianity as a legally recognized religion.

Constantine defeated his co-emperor Licinius at the battles of Adrianople and Chrysopolis, ending the Tetrarchy system. He became the sole ruler of the entire Roman Empire, reuniting the Western and Eastern halves under his control. This reunification was the last time the Roman Empire was united under a single ruler.

Constantine convened the First Council of Nicaea, the first ecumenical council of the Christian Church, to resolve the Arian controversy over the nature of Christ. The council produced the Nicene Creed, affirming the divinity of Christ and establishing a unified Christian doctrine. Constantine presided over the council.

Constantine dedicated the city of Constantinople (modern Istanbul) as the new capital of the Roman Empire, built on the site of the ancient Greek city of Byzantium. The city was strategically located on the Bosporus strait, controlling trade routes between Europe and Asia. It became the capital of the Eastern Roman Empire for over a thousand years.

Qin Shi Huang commissioned a vast mausoleum complex near Xi'an, guarded by thousands of life-sized terracotta soldiers, horses, and chariots. The project employed hundreds of thousands of workers and reflected his obsession with immortality and imperial power.

From 230 to 221 BCE, Ying Zheng led the Qin state in a series of campaigns that conquered the Han, Zhao, Wei, Chu, Yan, and Qi states. This unified China under a single ruler for the first time, ending the Warring States period.

Qin Shi Huang ordered the standardization of Chinese script, currency, and weights and measures across the unified empire. This facilitated administration, trade, and cultural integration, laying a foundation for future dynasties.

After conquering the last independent state, Ying Zheng declared himself Shi Huangdi (First Emperor), founding the Qin Dynasty. He adopted a new title to signify his supreme authority and initiated centralized imperial rule.

Qin Shi Huang ordered the connection and extension of existing northern fortifications to create a unified defensive wall against nomadic Xiongnu raids. This project involved massive conscripted labor and became the precursor to the later Great Wall.

On the advice of Li Si, Qin Shi Huang ordered the burning of historical records and philosophical texts not aligned with Legalist doctrine. He also had 460 Confucian scholars buried alive to suppress dissent and consolidate ideological control.