TheChristianization of Albania (Albanian:Krishtërizimi e Shqiperisë) was a process where the people who inhabited earlyAlbania duringlate antiquity and the earlymiddle ages converted toChristianity. Before this process of mass-conversion, a majority of the people in the lands of modern-day Albania either followedold Illyrian religion or practicedancient Greek religion. The christianization of Albania also had a large impact on the culture, history, society and government.
Christianity in Albania began when Christians arrived inIllyria soon after the time of Jesus, with a bishop being appointed in Dyrrhachium (Epidamnus) in 58 AD.[1] Christianity also came toEpirus nova, then part of the Roman province ofMacedonia.[2] In Romans 15:19,Saint Paul writes,"by the power of signs and wonders, and by the power of the Spirit of God. So from Jerusalem all the way around to Illyricum, I have fully proclaimed the gospel of Christ” which indicates that the lands ofIllyria had beenChristianized.[3][4] Since the 3rd and 4th century AD, Christianity had become the established religion inByzantium, supplanting pagan polytheism and eclipsing for the most part the humanistic world outlook and institutions inherited from the Greek and Roman civilizations. TheDurrës Amphitheatre(Albanian: Amfiteatri i Durrësit) is a historic monument from the time period located in Durrës, Albania, that was used to preach Christianity to civilians during that time. When theRoman Empire was divided into eastern and western halves in AD 395, Illyria east of the Drinus River (Drina betweenBosnia andSerbia), including the lands form Albania, were administered by the Eastern Empire but were ecclesiastically dependent onRome.
Though the country was in the fold ofByzantium, Christians in the region remained under the jurisdiction of thePope until 732. In that year the iconoclast Byzantine emperorLeo III, angered by archbishops of the region because they had supported Rome in theIconoclastic Controversy, detached the church of the province from the Roman pope and placed it under thepatriarch of Constantinople.
During theEast–West Schism, Christianity was divided between theRoman Catholic Church administrated by thePope and theEastern Orthodox Church. The region of southern Albania retained its ties toConstantinople, while the north reverted to the jurisdiction of Rome. This split marked the first significant religious fragmentation of the country. After the formation of the Slav principality of Dioclia (modernMontenegro), the metropolitan see ofBar was created in 1089, and dioceses in northern Albania (Shkodër,Ulcinj) became its suffragans. Starting in 1019, Albanian dioceses of the Byzantine rite were suffragans of the independentArchdiocese of Ohrid untilDyrrachion andNicopolis, were re-established as metropolitan sees. Thereafter, only the dioceses in inner Albania (Elbasan,Krujë) remained attached toOhrid. In the 13th century during theVenetian occupation, the Latin Archdiocese of Durrës was founded.

The church inAlbania during the Middle Ages was evenly split between the Roman Catholic and Eastern Orthodox churches. TheArbanasi (Old south Slavic term for Albanians) are recorded as being 'half-believers' and speaking their own language in aBulgarian text found in a Serbian manuscript dating to 1628; the text was written by an anonymous author that according toRadoslav Grujić (1934) dated to the reign ofSamuel of Bulgaria (997–1014), or possibly, according to R. Elsie, 1000–1018.[5] In 1166, we know thatprior Arbanensis Andrea andepiscopis Arbanensis Lazarus who were the Bishops ofArbanum participated in a Roman Catholic ceremony held inKotor.[6][7]
A year later in 1167,Pope Alexander III, in a letter directed to Lazarus, congratulates him for returning his bishopric to Catholic faith and invites him to acknowledge the archbishop ofRagusa as his superior. After some resistance from local officials, the bishopric of Arbanon was put under the direct dependence of the Pope, as documented in a Papal letter dated in 1188. Later according to the Geziq inscription,Demetrio Progoni, who had been reaccepted in the Catholic Church, had provided funds for the building of the church, which he might have planned to become the seat of theDiocese of Arbanum or a new diocese in the centre of his remaining domain. This is indicated by the fact that the new church was constructed on the site of an older church dedicated to St.Mary (Shën Mëri) but Progoni dedicated the new church toShën Premte, the patron saint of Arbanum.[8] He had maintained the semi-independence of this area under an agreement in which he accepted the high suzerainty of Zeta and the rulers of Zeta didn't get involved in internal affairs of the region in return.[8] In the inscription which also serves as the last will of Progoni, the church is dedicated to his people (nationi obtulit) and his successor is designated,Progon - son ofGjin Progoni - asprotosebastos.[8] The Greek-Albanian Lord ofKrujëGregorios Kamonas marriedKomnena Nemanjić and strengthened his ties with Serbia and securing Arbanon in an orthodox alliance thus putting Albania under orthodox control.[9] From the dissolution of the principality of Arbanon, Albania became under the rule of theAlbanian principalities who ruled under multiple different families and each family was either Roman Catholic, Eastern Orthodox orMuslim depending on what threatened their political influence and existence.