The Period of Disunion—often synonymous with the Three Kingdoms (三国)—spanned 220–280 CE, between the Eastern Han collapse and Jin reunification.
Constant warfare, shifting alliances, legendary figures (Zhuge Liang, Guan Yu, Zhou Yu). Cultural flowering: Romance of the Three Kingdoms (later novel), poetry, historiography, technology (wooden ox, repeating crossbow).
Ended 280 CE when Jin conquered Wu. Brief unity preceded the chaotic Sixteen Kingdoms & Northern/Southern Dynasties.