The papal will prevailed, and Methodius secured his freedom and his archiepiscopal authority over both Great Moravia and Pannonia, though the use of Slavonic for the mass was still denied to him. His authority was restricted in Pannonia when after Koceľ's death the principality was administered by German nobles; but Svatopluk now ruled with practical independence in Great Moravia, and expelled the German clergy. This apparently secured an undisturbed field of operation for Methodius, and the "Vita" (x.) depicts the next few years (873–879) as a period of fruitful progress. Methodius seems to have disregarded, wholly or in part, the prohibition of the Slavonic liturgy; and when Frankish clerics again found their way into the country, and the archbishop's strictness had displeased the licentious Svatopluk, this was made a cause of complaint against him at Rome, coupled with charges regarding the "Filioque".