88 BC

By place

Roman Republic

• The Social War ends with the defeat of the Italian allies by the Romans. Lucius Cornelius Sulla, age 50, becomes the first Roman commander to march on Rome with his army and to capture the city by force. This extraordinary act is prompted by his desire to maintain his consular command for the First Mithridatic War in Asia Minor.
• The First Roman Civil War starts with a democratic uprising led by Gaius Marius, but the democrats under the tribune P. Sulpicius Rufus are crushed by the conservatives under Sulla. Marius flees to Africa.
• First Civil War in Rome, between Marius and Sulla. Some Italian cities are destroyed: for instance, Forlì, rebuilt by the praetor Livius Clodius afterwards.
• The Dardani, Scordisci, and the Maedi attack the Roman province of Macedonia.

  Greece

• May - King Mithridates VI of Pontus invades Greece. Defeating the Roman forces four times in succession, he conquers Bithynia, Phrygia, Mysia, Lycia, Pamphylia, Ionia and Cappadocia. The Roman province of Asia is dismantled. On the king's orders, the local authorities in every city of the province round up and put to death all resident Italians – men, women and children – in a single day. Plutarch says that 150,000 are killed, other sources calculate a figure of 80,000 people.