Cappadocia had been an important and reliable client kingdom of the Roman Empire. Ariarathid dynasty, one of the remnant states of the Alexander the Great’s Empire, was ruling the area. Cappadocia was an ally of Seleucid kingdom during Roman–Seleucid Wars.
Roman–Seleucid Wars resulted with the victory of the Roman Empire therefore Cappadocians turned into Roman allied in the east. Mithridates VI ordered the assassination of Cappadocian Ariarathid king druing the Mithridatic Wars. This resulted with the invasion of Cappadocia by Pontus and freeing of Cappadocia by the Roman Empire several time.
Cappadocia stayed as an important Roman client kingdom till the era of Emperor Tiberius. Tiberius didn’t like Ariarathid rulers of Cappadocia since they showed their favor to Gaius Caesar earlier. Tiberius annexed Cappadocia completely into the Roman Empire by turning the kingdom into the ”Roman Province of Cappadocia”.
Caesarea, modern Turkish city of Kayseri, became the capital of the Roman province of Cappadocia. The Province became a nesting ground for early Christian leaders such as Basil of Caesarea, Gregory of Nazianzos and Gregory of Nyssa. Cappadocia went on to exist during late Roman times and Byzantine Empire till the invasions destroyed the province.