284 BC
Year 284 BC was a year of the pre-Julian Roman calendar. At the time it was known as the Year of the Consulship of Tucca and Denter/Dentatus (or, less frequently, year 470 Ab urbe condita). The denomination 284 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
Events
By place
Roman Republic
The Gallic tribe called the Senones, who has settled on the Adriatic coast north of Picenum, attacks Arretium in Etruria. While attempting to relieve this allied city, the Romans under the command of Lucius Caecilius Metellus Denter suffer a costly defeat in the Battle of Arretium. Aroused by this disaster, a Roman army under Manius Curius Dentatus invades the Senones' territory, defeating them and driving them out of the Italian peninsula.
Greece
Pyrrhus of Epirus is driven out of Macedonia and back into Epirus by Lysimachus.
Asia Minor
Ptolemy I's eldest (legitimate) son, Ptolemy Keraunos, whose mother, Eurydice, the daughter of Antipater, had been repudiated by the new King Ptolemy II, flees Egypt to the court of Lysimachus, the king of Thrace, Macedon and Asia Minor.