A considerable share of the Bulgarian cultural heritage accumulated during the Middle Ages consisted in icons. It is a truly stupendous and varied wealth, and many of its works rightly belong in the treasury of world classic art; indeed, the picture of Eastern Orthodox pictorial culture would be incomplete without these icons.
Icon painting in Bulgaria must have originated officially with the adoption of Christianity in 865 under Prince Boris (Mihail). Bulgaria, having adopted Christianity from the Byzantine church, was the first Slavic country to have mastered this significant mediaeval art and taken part in spreading it. Soon after 865 numerous churches an monasteries were built in the Bulgarian capitals Pliska and especially Preslav; in the 9th and 10th century the construction of churches spread throughout the country. All these places of worship were decorated with murals and icons. Preslav thus emerged as an important centre of art, where painted glazed ceramics, a technical variety of ecclesiastical painting, was mass-produced. Preslav ceramic icons, the oldest Bulgarian icons found so far, were also a very interesting manifestation of mediaeval Balkan art.