Sicily

• The Roman advance continues westward from Agrigentum with their forces relieving the besieged cities of Segesta and Macella. These cities have sided with the Roman cause, and have come under Carthaginian attack for doing so.
• Hannibal Gisco returns to fight in Sicily as the admiral in charge of the Carthaginian fleet in the Strait of Messina. With the Romans about to launch their first ever navy, Carthage is determined that this innovation be thwarted. Gisco defeats part of the Roman fleet and captures the Roman consul Gnaeus Cornelius Scipio Asina in an encounter near Lipari; the consul's nickname Asina (which means donkey) is earned in this encounter. However, this Carthaginian victory is of limited practical value as the bulk of the Roman fleet continues to manoeuvre in the surrounding waters.
• Confident in Carthage's superiority at sea, Hannibal Gisco deploys his ships for the Battle of Mylae in the traditional long line arrangement. Although inexperienced in sea battles, the Romans, led by consul Gaius Duilius Nepos, heavily defeat the Carthaginian fleet, mainly due to the innovative use of land tactics in naval warfare (including the use of the grappling irons and the corvus boarding bridge).
• Having lost the confidence of his peers, Hannibal Gisco is subsequently executed for incompetence shortly afterwards, together with other defeated Punic generals.
• In the north of Sicily, the Romans, with their northern sea flank secured by their naval victory in the Battle of Mylae, advance toward Thermae. They are defeated there by the Carthaginians under Hamilcar.

Egypt

• Callimachus of Cyrene, learned poet and grammarian, becomes chief librarian at the Library of Alexandria.

China

• Battle of Changping between the state of Qin and state of Zhao:

• Frustrated with the stalemate and encouraged by Qin spies, King Xiaocheng of Zhao replaces general Lian Po with the less cautious Zhao Kuo. Hearing of this, King Zhaoxiang of Qin secretly sends the famous general Bai Qi to take control of the Qin army.
• The Qin army under Bai Qi destroys the army of Zhao, establishing Qin's military superiority over all other Chinese states during the Warring States period. The battle takes place near modern-day Gaoping in Shanxi and hundreds of thousands of soldiers from Zhao are executed after the battle.^[1]