Before the Pope could claim to be supreme administrator within the Church it was necessary to deprive all other ecclesiastical officers of their independence. The custom of the gift of the pall to archbishops who exercised the office of Metropolitans had already made these highest officers of all into little more than delegates of the Papacy. Gregory VII failed in his attempt to force them to come in person to Rome in order to receive the pall. He succeeded, however, in imposing upon them an oath which, founded upon the oath of fealty, made their position analogous to that of a feudal vassal. By this a Metropolitan swore to be faithful to St. Peter and the Pope and his successors who should have been canonically elected; that he would be no party to violence against the Pope; that he would attend in person or by representatives at every synod to which the Pope summoned him; that, saving the rights of his Order, he would help to defend the Papacy and all its possessions and honours; that he would not betray any trust reposed in him by the Pope; that he would honourably treat the papal legate; that he would not knowingly communicate with excommunicates; that when asked he would faithfully help the Roman Church with a force of soldiers. To this was often added an undertaking that he would appear at Rome himself or by a representative at stated intervals; that he would cause his suffragans at their consecration to take an oath of obedience to the Roman pontiff; that he would not part with anything belonging to his official position without the knowledge of the Roman See. [Sidenote: Claim over bishoprics.] Gregory's successors imposed this oath by degrees on all bishops, and thus gradually substituted the Pope for the Metropolitan. The _Dictatus Papae_ claimed for the Pope the right of deposing or reinstating bishops without reference to a synod; of transferring a bishop from one see to another; of dividing a wealthy see or joining together poor bishoprics. It was the papal policy to champion the suffragans against the Metropolitans until the original metropolitical power of confirming the elections of their newly elected suffragans and consecrating them to the episcopal office was entirely superseded by the growing authority of the Pope. The right of confirmation implied the power of quashing an election, and this could easily grow into a power of direct appointment. This last power was only exercised habitually in certain cases--after a vacancy had lasted for a certain time; if the bishop had died at Rome; if the bishop had been transferred from one see to another. From the end of the eleventh century cases are found of bishops designated to be such, not only, according to the ancient formula, "by the grace of God," but also by that "of the Apostolic See," and such description becomes fairly common in the thirteenth century. [Sidenote: Claim over benefices.]