 During antiquity, Mariana was an important Roman military colony, founded in 93 BC by Gaius Marius.Christianity was implanted there early (proven by a Christian complex dating from the fourth century) and the diocese of Mariana was established in the fifth century, making it one of the first in Corsica's history.The diocese became the seat of the suffragan of the archdiocese of Pisa in 1092, like all bishoprics of Corsica.