Explanation: The council held from 879 to 880 is designated as the Eighth Ecumenical Council by the Eastern Orthodox Church, distinguishing it from the council of 869-870 recognized by the Roman Catholic Church.

Explanation: The council convened and took place between the years 879 and 880, not exclusively within 879.

Explanation: The council was attended by 383 bishops, not approximately 400.

Explanation: This council, recognized by the Catholic Church as the Eighth Ecumenical Council, deposed Photius and reinstated Ignatius as Patriarch.

Explanation: No, the council convened in 879 included representatives from all five patriarchates, including that of Rome, and was attended by 383 bishops.

Explanation: No, the Catholic Church recognizes the council of 869-870 as the eighth ecumenical council and does not include the council of 879-880 among its ecumenical councils.

Explanation: No, the Fifth Council of Constantinople is listed as the subsequent council, not the Second Council of Nicaea.

Explanation: Yes, the infobox explicitly states that the council is accepted by Eastern Orthodoxy.

Explanation: Yes, the Eastern Orthodox designation signifies their belief that the 879-880 council holds universal authority and effectively annulled or superseded the council of 869-870, which the Catholic Church recognizes as the eighth ecumenical council.

Explanation: The records indicate that exactly 383 bishops attended the Fourth Council of Constantinople (879-880).

Explanation: The council recognized by the Catholic Church as the eighth ecumenical council convened and concluded between the years 869 and 870.

Explanation: The council held from October 869 to February 870 resulted in the deposition of Photius and the reinstatement of Ignatius as Patriarch of Constantinople.

Explanation: By designating the 879-880 council as the Eighth Ecumenical Council, the Eastern Orthodox Church signifies their belief that this council superseded or annulled the council of 869-870, which the Catholic Church recognizes as the eighth.

Explanation: The Fifth Council of Constantinople is listed in the 'See also' section, indicating its chronological relationship to the Fourth Council of Constantinople.

Explanation: The Eastern Orthodox Church views the 879-880 council as ecumenical because they believe it annulled the council of 869, which had previously deposed Photius.

Explanation: No, the council confirmed the reinstatement of Photius I as the patriarch of Constantinople. The council of 869-870 had deposed him.

Explanation: The council was convened to resolve the dispute concerning the legitimacy of Photius I's patriarchate, which arose after Ignatius's deposition and subsequent reinstatement. The council confirmed Photius's legitimacy after Ignatius's death.

Explanation: Ignatius was indeed appointed Patriarch of Constantinople in an uncanonical manner, which precipitated the conflict and subsequent events leading to the councils.

Explanation: No, Photius's elevation was highly controversial due to Ignatius being deposed without a formal ecclesiastical trial and Photius's sudden rise to the patriarchal office.

Explanation: Yes, following the death of Patriarch Ignatius in 877, Photius I was reappointed Patriarch of Constantinople by Emperor Basil I.

Explanation: No, the Photian Schism occurred prior to the Council of 879-880, lasting roughly from 863 to 867, and led to the events surrounding the councils.

Explanation: No, Ignatius was deposed in 858 without a formal ecclesiastical trial. Photius was deposed by the council held in Constantinople from October 869 to February 870.

Explanation: Yes, the Photian Schism involved significant jurisdictional disputes between Rome and Constantinople, alongside theological disagreements.

Explanation: No, a patriarchate refers to the high office and jurisdiction of a patriarch, a supreme leader within the hierarchy of the Eastern Orthodox Church, not a minor bishopric.

Explanation: Yes, Ignatius of Constantinople was deposed and confined on the charge of treason, orchestrated by Caesar Bardas and Emperor Michael III.

Explanation: No, Photius was a renowned scholar and statesman, a kinsman of Caesar Bardas, before his elevation, not a simple monk.

Explanation: The central issue addressed and decided at the Fourth Council of Constantinople (879-880) was the confirmation of Photius I's legitimacy and his reinstatement as Patriarch of Constantinople.

Explanation: Following the death of Patriarch Ignatius in 877, Photius I was reappointed to the patriarchal office.

Explanation: In the context of the council's subject matter, 'patriarchate' refers to the high office, authority, and jurisdiction held by a patriarch, such as the Patriarch of Constantinople.

Explanation: Pope Nicholas I actually condemned Photius's appointment and supported Ignatius; therefore, this statement is not a reason for the controversy.

Explanation: Ignatius was deposed in 858 primarily because he opposed Caesar Bardas, who subsequently engineered his deposition on charges of treason.

Explanation: The deposition of Ignatius in 858 was highly controversial because it was carried out without a formal ecclesiastical trial, violating canonical procedures.

Explanation: The council was convoked by Emperor Basil I. Pope John VIII sent papal legates, but he did not convoke the council.

Explanation: No, Pope Nicholas I supported Ignatius and condemned Photius's election as uncanonical. He deposed Photius and reinstated Ignatius in 863.

Explanation: Yes, Photius, with imperial support, responded to Pope Nicholas I's condemnation by calling a council and excommunicating the Pope.

Explanation: Yes, Pope John VIII sent papal legates to the council, and they approved its proceedings, contributing to the complex reception of the council's acts.

Explanation: No, there is historical debate regarding Pope John VIII's acceptance. Some suggest qualified assent, while others dispute unconditional acceptance.

Explanation: No, the conflict was primarily about jurisdictional disputes and the legitimacy of Photius's patriarchate, not differing liturgical practices.

Explanation: Pope Nicholas I was the pontiff who initially condemned Photius's election and supported the cause of Ignatius.

Explanation: In response to Pope Nicholas I's condemnation, Photius, with the backing of Emperor Michael III, convened a council and excommunicated the Pope.

Explanation: A significant historical debate concerns whether Pope John VIII's acceptance of the council's acts was unconditional or qualified, with various scholars offering differing interpretations.

Explanation: A pallium is a sacred vestment worn by bishops and archbishops, symbolizing their authority and jurisdiction, which Pope John VIII sent as a gift to Photius.

Explanation: Scholarly debate primarily centers on the extent and nature of papal approval, specifically whether Pope John VIII's assent to the council's acts was unconditional or qualified.

Explanation: Papal legates, representing Pope John VIII, were present at the Council of 879-880 and approved its proceedings, although the Pope's ultimate acceptance of all acts remains debated.

Explanation: 'Qualified assent' implies that Pope John VIII agreed to the council's acts, but with specific reservations or conditions, indicating that his approval was not absolute.

Explanation: No, while the Filioque clause was addressed and implicitly condemned, the primary focus of the Fourth Council of Constantinople (879-880) was the resolution of the dispute concerning the legitimacy of Photius I's patriarchate.

Explanation: No, the council implicitly condemned the addition of the Filioque clause by condemning those who imposed their own invented phrases or falsified the ancient creed.

Explanation: No, Eastern Orthodox Christians argue that the council condemned the Filioque clause as heretical, not orthodox.

Explanation: No, Roman Catholics believe the Filioque clause is theologically correct, distinguishing its orthodoxy from the act of its addition to the creed.

Explanation: No, the term Filioque refers to the Latin phrase 'and the Son,' which was added to the Nicene Creed in the West. The council implicitly condemned this addition, but the term itself denotes the phrase, not the condemnation.

Explanation: The Council of 879-880 implicitly condemned the addition of the Filioque clause to the Nicene-Constantinopolitan Creed by denouncing those who imposed their own invented phrases or falsified the ancient creed.

Explanation: Eastern Orthodox Christians interpret the council's actions as a condemnation of the Filioque clause as heretical, a position strongly advocated by Photius.

Explanation: The council implicitly condemned the addition of the Latin phrase 'Filioque' (meaning 'and the Son') to the Nicene-Constantinopolitan Creed.

Explanation: The Eastern Orthodox Church interprets the council's actions as condemning the Filioque clause as heretical, whereas the Roman Catholic Church maintains the theological orthodoxy of the clause itself.

Explanation: Caesar Bardas engineered the deposition of Patriarch Ignatius, but Emperor Michael III was also instrumental in this action.

Explanation: Emperor Michael III, influenced by Caesar Bardas, supported the deposition of Ignatius and the subsequent elevation of Photius to the patriarchal throne.

Explanation: No, the murder of Bardas and Emperor Michael III by Basil the Macedonian led to Basil's rise to power. Basil then deposed Photius and reinstated Ignatius, prior to the 879 council.

Explanation: The Fourth Council of Constantinople (879-880) was convoked by Emperor Basil I.

Explanation: The deaths of Caesar Bardas and Emperor Michael III, key political figures who supported Photius, occurred prior to the 879 council, significantly altering the political landscape.

Explanation: Yes, following the council and dissatisfaction with the Pope's position, the Bulgarian Church reached an agreement with the Byzantines, aligning itself with Eastern Christianity.

Explanation: Yes, the infobox lists the restoration of Photius as a document or statement attributed to the 879-880 council.

Explanation: No, the Bulgarian ambassadors were dissatisfied with the Pope's position, which led them to seek and reach an agreement with the Byzantines.

Explanation: No, the council and the surrounding events, particularly the differing interpretations and recognitions, highlighted and arguably deepened the divergence between the Eastern and Western Churches.

Explanation: The Bulgarian Church aligned with the Byzantines because their ambassadors were dissatisfied with the positions offered by the Pope, leading them to seek and finalize an agreement with the Eastern Empire.

Explanation: The council's significance lies in its confirmation of Photius's patriarchate and the subsequent divergence in its recognition by the Eastern Orthodox and Roman Catholic Churches, contributing to historical divisions.