Peace of Antalcidas
Today known as the Varronian Chronology (from one of its early adopters, the famous antiquarian Marcus Terentius Varro), this chronology was made official by the early Roman Empire and has remained the standard ever since. However, for the years prior to 300 BC the Varronian Chronology is no longer considered correct. According to the respected Greek historian Polybius (ca. 200–118 BC) the sack of Rome by a Gaulish warband took place in the same year as the Peace of Antalcidas which was concluded in 387/386 BC. But according to the Varronian Chronology the Gaulish Sack happened three or four years earlier, in 390 BC.