Pope

The Christianization of Bulgaria was the process by which 9th-century medieval Bulgaria converted to Christianity. It reflected the need of unity within the religiously divided Bulgarian state as well as the need for equal acceptance on the international stage in Christian Europe. This process was characterized by the shifting political alliances of Boris I of Bulgaria (ruled 852–889) with the kingdom of the East Franks and with the Byzantine Empire, as well as his diplomatic correspondence with the Pope.

Because of Bulgaria's strategic position, the churches of both Rome and Constantinople each wanted Bulgaria in their sphere of influence. They regarded Christianization as a means of integrating Slavs into their region. After some overtures to each side, the Khan adopted Christianity from Constantinople in 870. As a result, he achieved his goal of gaining an independent Bulgarian national church and having an archbishop appointed to head it.

The Treaty of Edirne and the Peace of Szeged were two halves of a peace treaty between Sultan Murad II of the Ottoman Empire and King Vladislaus of the Kingdom of Hungary. Despot Đurađ Branković of the Serbian Despotate was a party to the proceedings. The treaty brought an end to the Christian crusade against the Ottomans with significant gains. Within a month Vladislaus abjured his oath at the urging of the papacy and the crusade continued. On 10 November 1444 it ended in disaster at the Battle of Varna where the crusaders were wiped out and Vladislaus killed.

The treaty was started in Edirne with discussions between Murad and Vladislaus' ambassador. Within a few days, it was sent to Szeged with Murad's ambassador, to be finalized and ratified by Vladislaus. Once it arrived, complications caused the negotiations to continue for several more days, and oaths were eventually given in Várad. The ratification took place on 15 August 1444 in Várad.

A European microstate or European ministate is a very small sovereign state in Europe. In modern usage, it typically refers to the six smallest states in Europe by area: Andorra, Liechtenstein, Malta, Monaco, San Marino, and Vatican City. Andorra, Liechtenstein, Monaco and Vatican City are monarchies (Vatican City is an elective monarchy ruled by the Pope). These states trace their status back to the first millennium or the early second millennium except for Liechtenstein, created in the 18th century.

Microstates are small independent states recognised by larger states. According to the qualitative definition suggested by Zbigniew Dumieński (2014), microstates can also be viewed as "modern protected states, i.e. sovereign states that have been able to unilaterally depute certain attributes of sovereignty to larger powers in exchange for benign protection of their political and economic viability against their geographic or demographic constraints."

The Diocese of Rome (Latin: Dioecesis Urbis seu Romana; Italian: Diocesi di Roma) is a Latin diocese of the Catholic Church under the direct jurisdiction of the pope, who is Bishop of Rome and hence the supreme pontiff and head of the worldwide Catholic Church. As the Holy See, the papacy is a sovereign entity with diplomatic relations, and it has civil jurisdiction over Vatican City (located geographically within the city of Rome). The Diocese of Rome consists of two geographical jurisdictions: the Vicariate of Rome, and the small Vicariate of Vatican City. It is the metropolitan diocese of the Province of Rome, an ecclesiastical province in the Ecclesiastical Region of Lazio in Italy. According to Catholic tradition, the first bishop of Rome was Saint Peter during the first century.

Historically, many Rome-born men – as well as others born elsewhere on the Italian peninsula – served as bishops of Rome. Since 1900, however, there has been only one Rome-born bishop of Rome, Pius XII (1939–1958). In addition, throughout history, non-Italians have served as bishops of Rome, beginning with the first of them according to Catholic tradition – Saint Peter.

The Holy See exercised temporal power, as distinguished from its spiritual and pastoral activity, while the pope ruled the Papal States in central Italy. The Papal States ceased to exist following the capture of Rome in 1870 by the Royal Italian Army, after which its remaining territories were annexed to the Kingdom of Italy. The Lateran Treaty of 1929 later established the Vatican City, a small city-state where the Holy See currently exercises temporal powers.

A sacerdotal state is a state whose head is also an ecclesiastical leader designated by a religious body. An example of this kind of state is the Vatican City: its heads of state, the popes of the Catholic Church, have governed papal lands distinct from secular authority since the establishment of the Papal States in the 8th century AD. Andorra operates under a semi-sacerdotal system, as one of its co-heads of state is the bishop of Urgell, while the other is the head of state of France. However unlike the Vatican, the co-princes of Andorra are ceremonial and not closely involved in the government.

In the past, bishops commonly assumed temporal as well as spiritual authority and ruled as prince-bishops. This occurred, for example, in the Holy Roman Empire, where three of the seven imperial electors were prince-archbishops (those of Trier, Mainz and Cologne). After the 1648 Peace of Westphalia certain prince-bishoprics became bi-confessional and alternated between governance by Catholic bishops and by Protestant administrators.

The Avignon Papacy (Occitan: Papat d'Avinhon; French: Papauté d'Avignon) was the period from 1309 to 1376 during which seven successive popes resided in Avignon (at the time within the Kingdom of Arles, part of the Holy Roman Empire, now part of France) rather than in Rome. The situation arose from the conflict between the papacy and the French crown, culminating in the death of Pope Boniface VIII after his arrest and maltreatment by agents of Philip IV of France. Following the subsequent death of Pope Benedict XI, Philip pressured a deadlocked conclave to elect the Archbishop of Bordeaux as pope Clement V in 1305. Clement refused to move to Rome, and in 1309 he moved his court to the papal enclave at Avignon, where it remained for the next 67 years. This absence from Rome is sometimes referred to as the "Babylonian captivity" of the Papacy (cf. Italian cattività avignonese, i.e. "Avignonese captivity").

A total of seven popes reigned at Avignon, all French, and all under the influence of the French Crown. In 1376, Gregory XI abandoned Avignon and moved his court to Rome, arriving in January 1377. After Gregory's death in 1378, deteriorating relations between his successor Urban VI and a faction of cardinals gave rise to the Western Schism. This started a second line of Avignon popes, subsequently regarded as illegitimate. The last Avignon antipope, Benedict XIII, lost most of his support in 1398, including that of France. After five years besieged by the French, he fled to Perpignan in 1403. The schism ended in 1417 at the Council of Constance.

The Apostolic Palace is the official residence of the Pope, the head of the Catholic Church, located in Vatican City. It is also known as the Papal Palace, the Palace of the Vatican and the Vatican Palace. The Vatican itself refers to the building as the Palace of Sixtus V, in honor of Pope Sixtus V, who built most of the present form of the palace.

The building contains the papal apartments, various offices of the Catholic Church and the Holy See, private and public chapels, the Vatican Museums, and the Vatican Library, including the Sistine Chapel, Raphael Rooms, and the Borgia Apartments. Tourists can see this part of the palace, but other parts, such as the Sala Regia (Regal Room) and Cappella Paolina, had long been closed to tourists, though the Sala Regia allowed occasional tourism by 2019. The Scala Regia (Regal Staircase) can be viewed from one end and used to enter the Sala Regia. The Cappella Paolina remains closed to tourists.

The Quirinal Palace (Italian: Palazzo del Quirinale [paˈlattso del kwiriˈnaːle]) is a historic building in Rome, Italy, the main official residence of the President of the Italian Republic, together with Villa Rosebery in Naples and the Tenuta di Castelporziano, an estate on the outskirts of Rome, some 25 km (16 mi) from the centre of the city. It is located on the Quirinal Hill, the highest of the seven hills of Rome in an area colloquially called Monte Cavallo. It has served as the residence for thirty popes, four kings of Italy and twelve presidents of the Italian Republic.

The Quirinal Palace, originally a papal residence built by Pope Gregory XIII, was selected by Napoleon to be his residence par excellence as emperor. However, he never stayed there because of the French defeat in 1814 and the subsequent European Restoration.

An emperor (from Latin: imperator, via Old French: empereor) is the (male) ruler of an empire. Empress, the female equivalent, may indicate an emperor's wife (empress consort), mother/grandmother (empress dowager/grand empress dowager), or a woman who rules in her own right and name (empress regnant or suo jure). Emperors are generally recognized to be of the highest monarchic honour and rank, surpassing king. In Europe, the title of Emperor has been used since the Middle Ages, considered in those times equal or almost equal in dignity to that of Pope due to the latter's position as visible head of the Church and spiritual leader of the Catholic part of Western Europe. The emperor of Japan is the only currently reigning monarch whose title is translated into English as "Emperor", although he no longer reigns over an empire.

Both emperors and kings are monarchs or sovereigns, both emperor and empress are considered monarchical titles. In as much as there is a strict definition of emperor, it is that an emperor has no relations implying the superiority of any other ruler and typically rules over more than one nation. Therefore, a king might be obliged to pay tribute to another ruler, or be restrained in his actions in some unequal fashion, but an emperor should in theory be completely free of such restraints. However, monarchs heading empires have not always used the title in all contexts—the British sovereign did not assume the title Empress of the British Empire even during the incorporation of India, though she was declared Empress of India.