Emperor Justinian and Papal primacy

Emperor Justinian is often known for his Erastianism aka Caesaropapism where essentially the government controls the Church (he appointed and deposed bishops at will, kidnapped, and imprisoned others, his wife deposed in effect Pope St. Silverius). Yet, he is venerated as a saint by Byzantine Christianity alongside the similarly troublesome Emperor Constantine the Great. However, despite Justinian's deposition and replacement of bishops, he also seemed to recognize the authority of the Roman See.

Justinian in a letter to the Patriarch of Constantinople (who he illicitly called ecumenical) states the Pope of Rome is the "head of the most holy priest of God" and wanted to protect unity with the Papacy:

...We issued a divine edict, also known to Your Holiness, in which We refuted the madness of the heretics; yet We neither have changed nor now change nor have neglected the status of the Church, which has hitherto prevailed with the help of God, as Your Blessedness also knows; but in all things We have protected the unity of the most holy churches with the most holy Pope and Patriarch of ancient Rome, to whom We have written a similar letter.  For We suffer nothing concerning the state of the Church to be withheld from His Blessedness, inasmuch as he is the head (κεφαλή) of the most holy priests of God, and because whenever heretics have arisen in those parts (the West), they have been restrained by the counsel and the correct judgment of his Venerable See.--The Codex of Justinian, First Book, 1.6-1.7, page 25, Letter of Emperor Justinian to Patriarch Epiphanius of Constantinople, March 26, AD 533. 

..δπερ καί ή σή γινώσκει άγιωσύνη, δι’ οΰ τήν τών αιρετικών μανίαν ήλέγξαμεν, ούδέν παντελώς έναλλάξαντες ή έναλλάττοντες ή παρεξελθόντες τής μέχρι νϋν σύν θεώ κρατούσης εκκλησιαστικής καταστάσεως, καθά και ή σή γινώσκει μακαριστής, άλλα διά πάντων φυλάττοντες τήν κατάστασιν τής ένώσεως τών άγιωτάτων εκκλησιών τής πρός τόν άγιώτατον πάπαν τής πρεσβυτέρας 'Ρώμης κα'ι πατριάρχην, πρός δν καί τά δμοια τούτοις γεγράφαμεν. Ούτε γάρ άνεχόμεθά τι τών εις εκκλησιαστικήν όρώντων κατάστασιν μή καί τή αυτού άναφέρεσθαι μακαριότητι, ώς κεφαλή ουση πάντων τών άγιωτάτων του θεοΰ ιερέων, καί επειδή, οσάκις έν τούτοις τοϊς μέρεσιν αιρετικοί άνεφύησαν, τή γνώμη καί ορθή κρίσει έκείνου τοΰ σεβασμίου θρόνου κατηργήθησαν. 3· Έκ γάρ τών παρουσών θείων ήμών συλλαβών μαθήσεται ή σή άγιωσύνη τά παρ’ ήμών προτεθειμένα, έφ’ ω τούς έπιχειροΰντας πονηρώς νοεΐν ή έρμηνεύειν τά παρ’ ήμών όρθώς έν τώ ήδίκτω λεχθέντα έκ τών παρουσών θείων ήμών έλέγχεσθαι συλλαβών. --The Codex of Justinian, First Book, 1.6-1.7, page 24, Letter of Emperor Justinian to Patriarch Epiphanius of Constantinople, March 26, AD 533. (Greek text)

In a letter to Pope John II, Emperor Justinian stated he made the Eastern churches subject and united to the Papacy, again stating the Papacy is "the head of all holy churches."

Rendering honor to the Apostolic See and to Your Holiness, which has always been and remains Our wish, as it ought to be, and honoring Your Blessedness as a father, We hasten to bring to the notice of Your Holiness everything concerning the status of the churches, since We have always greatly desired to preserve the unity of Your Apostolic See and to maintain the status of the Holy Churches of God, as it has heretofore prevailed and continues undisturbed without the interference of anything to the contrary. 9. We have therefore hastened to make all priests of the whole Orient subject to the See of Your Holiness and to unite them with it. 10. And We therefore deemed it necessary to bring to the notice of Your Holiness what action presently has been taken here, although it is clear and unquestioned and has ever been resolutely observed and preached by all priests in accord with the teaching of Your Apostolic See. For We permit no action to be taken concerning the status of the churches, however clear and unquestioned it may be, but that it should come to the notice of Your Holiness, because You are the head of all holy churches. For in all ways, as stated, We strive to increase the honor and authority of Your See.--The Codex of Justinian, First Book, 1.8, page 34-35, Letter of Emperor Justinian to Pope John II, June 6, AD 533. 

Reddentes honorem apostolicae sedi et vestrae sanctitati, quod semper nobis in voto fuit et est, ut decet, patrem honorantes vestram beatitudinem omnia, quae ad ecclesiarum statum pertinent, festinamus ad notitiam deferre vestrae sanctitatis, quoniam semper magnum nobis fuit studium unitatem vestrae apostolicae sedis et statum sanctarum dei ecclesiarum custodiri, qui hactenus obtinet et incommote permanet nulla intercedente contrarietate. 9. Ideoque omnes sacerdotes universi orientalis tractus et subicere et unire sedi vestrae sanctitatis properavimus. 10. Et in praesenti ergo quae hic commota sunt, quamvis manifesta et indubitata sint et secundum apostolicae vestrae sedis doctrinam ab omnibus semper sacerdotibus firme custodita et praedicata, necessarium duximus, ut ad notitiam vestrae sanctitatis perveniant. 11. Nec enim patimur quicquam, quod ad ecclesiarum statum pertinet, quamvis manifestum et indubitatum sit, quod movetur, ut non etiam vestrae innotescat sanctitati, quia caput est omnium sanctarum ecclesiarum, per omnia enim, ut dictum est, properamus honorem et auctoritatem crescere vestrae sedis. --The Codex of Justinian, First Book, 1.8, page 34-35, Letter of Emperor Justinian to Pope John II, June 6, AD 533. (Latin text)

In the same letter it states he follows the Roman church "in all things":

This then is Your true faith, this Your unshakeable religion; this all the fathers of blessed memory, as We have said, and the heads of the Roman Church, whom We follow in all things; this the Apostolic See has preached to this day and unshakeably guarded. Every opponent of this confession, of this faith, has declared himself alien to Holy Communion, alien to the Catholic Church--The Codex of Justinian, First Book, 1.8, page 38, Letter of Emperor Justinian to Pope John II, June 6, AD 533.

Haec est igitur vestra vera fides, haec certa religio, hoc beatae recordationis, ut diximus, patres omnes praesulesque Romanae ecclesiae, quos in omnibus sequimur, hoc sedes apostolica praedicavit hactenus et inconvulse custodivit: huic confessioni, huic fidei quisquis contradictor extiterit, alienum a sancta communione, alienum se ipse ab ecclesia indicavit esse catholica. --The Codex of Justinian, First Book, 1.8, page 37, Letter of Emperor Justinian to Pope John II, June 6, AD 533.

 In the same codex Justinian contained Pope John II's letter to the Emperor, where the pope asserts he is the read of the churches:

Amid the glowing praise of the wisdom of Your Mildness, Most Christian of Emperors, there shines with an especially pure light, like that of a star, the fact that You, in Your zeal for the faith and Your Christian charity, well instructed in the teachings of the Church, keep (Your) reverence of the See of Rome, submit everything to it, and lead everything to its unity; to whose founder, that is, the First of the Apostles, Our Lord gave this precept: "Feed my sheep.”[John 21] That this See is truly the head of all churches, both the regulations of the fathers and the statutes of emperors declare, as the most reverent utterances of Your Piety also attest.--Letter of Pope John II to Emperor Justinian, First Book, 1.7-8, page 31

Inter claras sapientiae mansuetudinis vestrae laudes, christianissime principum, puriore luce tamquam aliquod sidus irradiat, quod amore fidei, quod caritatis studio, edocti ecclesiasticis disciplinis, Romanae sedis reverentiam conservatis et ei cuncta subicitis et ad eius deducitis unitatem, ad cuius auctorem, hoc est apostolorum primum, domino loquente praeceptum est: ‘pasce oves meas’. i. Quam esse omnium vere ecclesiarum caput et patrum regulae et principum statuta declarant et pietatis vestrae reverentissimi testantur affatus --Letter of Pope John II to Emperor Justinian, First Book, 1.7-8, page 30

To be continued...