The Three Kingdoms period of Chinese history was a turbulent period in Chinese history that lasted from 220-280 CE. It was marked by warfare, civil turmoil and the breakdown of centralized authority. The main cause of the period derived from the fall of the Han Dynasty in 220 CE and its subsequent replacement by the three distinct states of Wei, Shu, and Wu.
The decline of the Han Dynasty can be traced to many factors, including a gradual weakening of the central government, external pressures from nomadic tribes, and the death of several powerful rulers. In the early years of the dynasty, the Emperor Wu had strengthened centralized control, managing to maintain order and stability for much of his reign. He also helped expand and solidify the Chinese borders, and he successfully waged wars against the nomadic Xiongnu tribes of Central Asia.
However, Wu’s successors were far less successful at sustaining his achievements. Powerful families emerged with the intention of controlling their own regions, and the central government became increasingly weak. This fragmentation weakened the country and left it open to attack from external forces, notably the Xiongnu, who began to encroach on Chinese territory.
Internal rivalries, especially between the powerful warlords of the time, also contributed to the weakening of the central government. Warlordism was rampant during this era, as many of these warlords sought to gain power for themselves and their own territories. This struggle for power amongst these warlords caused much destruction and destabilization within the country and further weaken the central government.
Perhaps the most significant cause of the Three Kingdoms period was the death of Emperor Ling in 189 CE. Ling had been the last ruler of the Han Dynasty, and his death caused a power vacuum which no single ruler was able to fill. This allowed the warlords and their respective factions to gain control of their own territories. They formed the three distinct states of Wei, Shu, and Wu, and the era of the Three Kingdoms period began.
Ultimately, the complex nature of the Three Kingdoms period was the result of a combination of factors. These include an already weakened central government, external pressures from nomadic tribes, internal rivalries among the warlords, and the death of Emperor Ling. Over the course of the next several decades, the three distinct states of Wei, Shu, and Wu would compete for control, leading to a period of constant warfare and civil unrest.