Centuries: 4th century BC - 3rd century BC - 2nd century BC
- Sieve of Eratosthenes developed.
- The Roman Lucius Coruncanius is assaulted and killed while on a diplomatic mission to Queen Teuta, an event leading to the First Illyrian War.
- Temple of Horus built by Ptolemy III of Egypt.
- Hasdrubal succeeds his father-in-law Hamilcar Barca, who had been slain in battle, as ruler of Carthaginian Spain.
- State of Qin conquered the state of Han in China.