Kammala jumla mai zuwa: An ce gabatarwar Kiristanci a Zakynthos ya faru ne lokacin da Saint Mary Magdalene ko Saint Berenice suka ziyarci tsibirin a karni na 1 AD a kan hanyarsu zuwa Roma. A cikin 324 AD, Zakynthos ya zama wani ɓangare na Prefecture na Illyricum. Yayin da Daular Roman ta rabu zuwa Gabas da Yammacin rabi kuma rabin yamma ya ragu, Zakynthos da sauran Tsibirin Ionian, yanzu suna kan iyakar Roman Empire na Gabas ko Byzantine, sun zama masu rauni ga hare-hare daga kabilun barbari da 'yan fashi. A cikin 466 AD, Sarkin Vandal Genseric ya kwashe Zakynthos kuma ya kama membobin Zakynthian 500 na fitattun mutanen yankin. Daga baya an yi amfani da tsibirin a matsayin tashar jiragen ruwa a lokacin Belisarius '
yaƙi da Vandals.