 It was generally believed that shortly after this the see was transferred from Windisch to Konstanz, until investigations, particularly by Marius Besson, made it probable that, between 549 and 585, the see was divided and the real seat of the bishops of Windisch transferred to Avenches (Aventicum), while the eastern part of the diocese was united with the Diocese of Konstanz.According to the Synod of Mâcon of 585 St. Marius seems to have been the first resident Bishop of Avenches.The Chartularium of Lausanne affirms that St. Marius was born in the Burgundian Diocese of Autun about 530, was consecrated Bishop of Avenches in May, 574, and died 31 December, 594.