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. Background When Khan Boris began his reign in 852, the international situation in Southeast Europe was characterized by a race for influence in the region, both cultural and political. The conflict with the Byzantine Empire for domination over the Slavic tribes in modern-day Macedonia and Thrace was still far from being resolved. In the middle Danube region, Bulgaria's interests crossed with those of the emerging kingdom of the East Franks and the principality of Great Moravia. It was about that period when Croatia emerged on the international scene, carrying its own ambitions and demands for territories in the region. On a larger scale, the tensions between Constantinople and Rome were tightening. Both centres were competing to lead the Christianization that would integrate the Slavs in South and Central Europe. The Bulgarian Khanate and the Kingdom of the East Franks had established diplomatic relations as soon as the 20s and 30s of the 9th century. In 852, at the beginning of the reign of Khan Boris, a Bulgarian embassy was sent to Mainz to tell Louis II of the change of power in Pliska, the Bulgarian capital. Most probably the embassy also worked to renew the Bulgarian-German alliance. Initial setbacks Some time later, Khan Boris concluded an alliance with Rastislav of Moravia (846–870) instigated by the King of the West Franks, Charles the Bald (840–877). The German Kingdom responded by attacking and defeating Bulgaria, forcing Khan Boris to later re-establish an alliance with the German king directed against Great Moravia, a Byzantine ally. The