Roman province of Bithynia and Pontus was located on the Black Sea coast of Anatolia, today’s Turkey. The kingdom of Bithynia was made into a province in 74 BC and the kingdom of Pontus was annexed to Bithynia in 63 BC. Thus resulting into the forming of Bithynia and Pontus province.
Bithynia wished to join into the Roman Empire to gain support against Pontus Kingdom. This resulted with the Third Mithridatic War. Mithridates VI of Pontus rallied his allies into the war against Rome and nearly succeeded pushing the Romans out of Asia Minor. But in the end Pompey was sent to finish the rebellion. Mithridates VI of Pontus was assassinated and Pontus Kingdom ceased to exist.
Nicomedia, modern Izmit town of Turkey, became the capital of the Bithynia and Pontus province. Province went on to exist as it is till administrative reforms of emperor Diocletian on the fourth century.
