217 BC

217 BC was a year of significant events in the Roman Republic and elsewhere, particularly marked by military conflict and political developments.

• Second Punic War: The dominant event of the year was the continuation of the Second Punic War between Rome and Carthage. The year is primarily remembered for the Battle of Lake Trasimene, where Hannibal ambushed and decisively defeated a Roman army under Gaius Flaminius. This victory gave Hannibal significant strategic advantages in Italy, though it did not end the war. Following the Trasimene disaster, Quintus Fabius Maximus Verrucosus was appointed dictator in Rome. Fabius adopted a strategy of attrition and avoidance of direct confrontation, known as the Fabian strategy, to wear down Hannibal's forces.

• Illyrian Wars: In Illyria, Demetrius of Pharos continued to challenge Roman authority, leading to further tensions. Roman activity was limited due to the pressing war with Carthage.

• Seleucid Empire: Antiochus III the Great continued his eastern campaigns, attempting to restore the Seleucid Empire's former territories.

• Other Events: Records of events outside of the Mediterranean region are less detailed for this period. Further research might be required to identify significant events in other parts of the world during this year.