Romance and Wars of the Three Kingdoms
A famous fourteenth century novel, The Romance of the Three Kingdoms, described the times of the Three Kingdoms as a period of romance, heroism and chivalry. But it was hardly romantic for those who lived it. Of the three kingdoms, Wei had the strongest of military, a strength bolstered by its economy and water transport. The Kingdom of Shu was more sparsely populated, an area of mostly forest, and with many people who were not Chinese.
In 263, Wei overwhelmed and absorbed Shu, leaving Wei and Wu as rivals. Then Wei's ruler was overthrown from within, one of his generals beginning a dynasty of his own, and, thirty-six years later, in 280, his offspring, Jin Wudi, overpowered and annexed the kingdom of Wu. China was now nominally united, and Jin Wudi extended his power northward to central Korea and southward into Annam. The cycle between unity and disintegration had swung back to unity. A new dynastry, called the Western Jin, had begun ruling China.
Forays against China by the Xiongnu and other tribal people ended for awhile. And the policy of settling tribal people within China was resumed. There was hope for peace, unity and prosperity, and, as early as 280, Jin Wudi began a program of disarmament. Troops were discharged, and metal weapons of value were melted down for coin. But Jin Wudi's attempt at disarmament proved of little benefit. Some discharged soldiers kept their weapons. Soldiers traded their weapons to the Xiongnu in exchange for land. And Princes in outlying areas did not disarm or disband their militias.
Jin Wudi was attempting a return to the greatest period of Han rule, back when peace brought China prosperity and the Han held strong central authority. Jin Wudi initiated reforms aimed at curbing dispersed power -- the power of great families. But these reforms failed. At his death in 290, China's great landlords still had private armies.
With Jin Wudi's death came the weakness that occasionally besets monarchies: Jin Wudi's son and successor, Jin Huidi was mentally deficient, and Jin Huidi's wife, Queen Jia, ruled in his place. She was fearful and began arresting and executing anyone whom she saw as a threat to her position. This included a rival faction within the royal family. Warfare erupted. Several dukes and thousands of others were murdered. Queen Jia failed to kill all her opponents, and, in the year 300, a prince named Lun led a coup that killed Queen Jia, the feebleminded emperor, and many others. Lun made himself emperor, and he in turn was killed by Prince Lui. In 302 he was killed by Prince Changsha, who in 303 was killed by a prince called Donghai. In 306, two more princes fell. Then came drought and famine. The central government had grown weak. The cycle of unity and disintegration had swung back to disintegration.