Decades: 270s BC 260s BC 250s BC 240s BC 230s BC - **220s BC** - 210s BC 200s BC 190s BC 180s BC 170s BC

Years: 230 BC 229 BC 228 BC 227 BC 226 BC - **225 BC** - 224 BC 223 BC 222 BC 221 BC 220 BC

- Seleucus III Ceraunus succeeds his father Seleucus II Callinicus as king of the Seleucid dynasty.
- Battle of Faesulae, Romans are defeated by the Gauls of Northern Italy.
- Erastothenes of Cyrene calculates the circumference of the Earth.
- Apollonius of Perga writes
*On Conic Sections*and names the ellipse, parabola, and hyperbola. - State of Qin conquered the state of Wei in China.

- Fan Ju
- Seleucus II Callinicus, king of the Seleucid dynasty. (riding accident)