Pope Zosimus A.C. 417, cited Proculus Bishop of Marseilles to appear before a Council at Rome for illegitimate Ordinations; and condemned him, as he mentions in several of his Epistles. Pope Boniface I. A.C. 419, upon a complaint of the Clergy of Valentia, against Maximus a Bishop, summoned the Bishops of all Gallia and the seven Provinces to convene in a Council against him; and saith in his Epistle, that his Predecessors had done the like. Pope Leo I. called a general Council of all the Provinces of Spain to meet in Gallaecia against the Manichees and Priscillianists, as he says in his decretal Epistle to Turribius a Spanish Bishop. And in one of his decretal Epistles to Nicetas Bishop of Aquileia, he commands him to call a Council of the Bishops of that Province against the Pelagians, which might ratify all the Synodal Decrees which had been already ratified by the See of Rome against this heresy. And in his decretal Epistle to Anastasius Bishop of Thessalonica, he ordained that Bishop should hold two Provincial Councils every year, and refer the harder causes to the See of Rome: and if upon any extraordinary occasion it should be necessary to call a Council, he should not be troublesome to the Bishops under him, but content himself with two Bishops out of every Province, and not detain them above fifteen days. In the same Epistle he describes the form of Church-Government then set up, to consist in a subordination of all the Churches to the See of Rome: De qua forma, saith he, Episcoporum quoque est orta distinctio, & magna dispositione provisum est ne omnes sibi omnia vindicarent, sed essent in singulis Provinciis singuli quorum inter fratres haberetur prima sententia, & rursus quidam in majoribus urbibus constituti sollicitudinem sumerent ampliorem, per quos ad unam Petri Sedem universalis Ecclesiae cura constueret, & & nihil usque a suo capite dissideret. Qui ergo scit se quidusdam esse praepositum, non moleste ferat aliquem sibi esse praepositum; sed obedientiam quam exigit etiam ipse dependat; et sicut non vult gravis oneris sarcinam ferre, ita non audeat aliis importabile pondus imponere. These words sufficiently show the monarchical form of government then set up in the Churches of the Western Empire under the Bishop of Rome, by means of the imperial Decree of Gratian, and the appeals and decretal Epistles grounded thereupon.

The same Pope Leo, having in a Council at Rome passed sentence upon Hilary Bishop of Arles, for what he had done by a Provincial Council in Gallia, took occasion from thence to procure the following Edict from the Western Emperor Valentinian III. for the more absolute establishing the authority of his See over all the Churches of the Western Empire.

Impp. Theodosium & Valentinianus AA. Aetio Viro illustri, Comiti & Magistro utriusque militiae & Patricio.

Certum est & nobis & imperio nostro unicum esse praesidium in supernae Divinitatis favore, ad quem promerendum praecipue Christiana fides & veneranda nobis religio suffragatur. Cum igitur Sedis Apostolicae Primatum sancti Petri meritum, qui princeps est Episcopalis coronae & Romanae dignitas civitatis, sacrae etiam Synodi firmavit auctoritas: ne quid praeter auctoritatem Sedis istius illicitum praesumptio attemperare nitatur: tunc enim demum Ecclesiarum pax ubique servabitur, si Rectorem suum agnoscat Universitas. Haec cum hactenus inviolabiliter fuerint custodita, Hilarius Arelatensis, sicut venerabilis viri Leonis Romani Papae fideli relatione comperimus, contumaci ausu illicita quaedam praesumenda tentavit, & ideo Transalpinas Ecclias abominabilis tumultus invasit, quod recens maxime testatur exemplum. Hilarius enim qui Episcopus Arelatensis vocatur, Ecclesiae Romanae urbis inconsulto Pontifice indebitas sibi ordinationes Episcoporum sola temeritate usurpans invasit. Nam alios incompetenter removit; indecenter alios, invitis & repugnantibus civibus, ordinavit. Qui quidem, quoniam non facile ab his qui non elegerant, recipiebantur, manum sibi contrahebat armatam, & claustra murorum in hostilem morem vel obsidione cingebat, vel aggressione reserabat, & ad sedem quietis pacem praedicaturus per bella ducebat. His talibus contra Imperii majestatem, & contra reverentiam Apostolicae Sedis admissis, per ordinem religiosi viri Urbis Papae cognitione discussis, certa in eum, ex his quos male ordinaverat, lata sententia est. Erat quidem ipsa sententia per Gallias etiam sine Imperiali Sanctione valitura: quid enim Pontificis auctoritate non liceret? Sed nostram quoque praeceptionem haec ratio provocavit. Nec ulterius vel Hilario, quem adhuc Episcopum nuncupare sola mansueta Praesulis permittit humanitas, nec cuiquam alteri ecclesiasticis rebus arma miscere, aut praeceptis Romani Antistitis liceat obviare: ausibus enim talibus fides & referentia nostri violatur Imperii. Nec hoc solum, quod est maximi criminis, submovemus: verum ne levis saltem inter Ecclesias turba nascatur, vel in aliquo minui religionis disciplina videatur, hoc perenni sanctione discernimus; nequid tam Episcopis Gallicanis quam aliarum Provinciarum contra consuetudinem veteram liceat, sine viri venerabilis Papae Urbis aeternae auctoritate, tentare. Sed illis omnibusque pro lege sit, quicquid sanxit vel sanxerit Apostolicae Sedis auctoritas: ita ut quisquis Episcoporum ad judicium Romani Antistitis evocatus venire neglexerit, per Moderatorem ejusdem Provinciae adesse cogatur, per omnia servatis quae Divi parentes nostri Romanae Ecclisiae detulerunt, Aeti pater carissime Augusti. Unde illustris & praeclara magnificentia tua praesentis Edictalis Legis auctoritate faciet quae sunt superius statuta servari, decem librarum auri multa protinus exigenda ab unoquoque Judice qui passus fuerit praecepta nostra violari. Divinitas te servet per multos annos, parens carissime. Dat. 8:Id. Jun. Romae, Valentiniano A.C.