The Battle of Chalcedon was a land and naval battle between the Roman Republic and King Mithridates VI of Pontus near the city of Chalcedon in 74 BC. It was the first major clash of the Third Mithridatic War. The Roman forces were led by Marcus Aurelius Cotta, one of the consuls for 74 BC, while Mithridates had the overall command of the Pontic forces. The Mithridatic forces were victorious on both land and sea.