The city

spolia: architectural materials from earlier monuments that are reused as building materials in a later period.
capital: uppermost part of a column acting as support for the architrave, usually decorated. The three basic types of capitals are the Doric, the Ionic and the Corinthian. In Byzantine times they were adorned with carvings and used in churches, being mostly variations of the Corinthian type.
basilica: type of large church, divided internally into three or more naves. The central nave was usually covered by a raised roof with windows that illuminated the space.
triconch: building with three apses.
single-lobed or single-light window: window with a single opening that forms an arc at the top.
double light or biforate window: window with two openings that form an arc at the top. The openings are usually separated by mullions.
ceramoplastic decoration: ceramic and plinth decorative elements inlayed on the exterior surfaces of church walls (bricks, meanders, crosses, diamonds, jagged strips, etc.)
frieze: architectural term used to describe the area of the church above the architrave. Friezes on ancient temples bore depictions of people, animals, or entire scenes from myths.
chrysobull: official public document or decree issued by the emperors of Byzantium, with an authenticating gold stamp on the silk band that accompanied it.

Procopius: Prolific Byzantine historian. Born in Caesarea ​​Palestinae, he studied rhetoric, sophistry and law. He moved to Constantinople at an early age, where he practiced as an orator and lawyer. He soon entered the circle of General Belisarius as secretary and advisor, and followed him on many campaigns. Procopius survived the great plague of Constantinople (541-542), which he described in detail. His writings are considered the most important source for the Justinian period, although admittedly he is not impartial towards the emperor; from a certain point onwards he seems to be unfavourably biased against both Justinian and Theodora. From 549 onwards Procopius lived permanently in Constantinople, though no information has survived on the final years of his life.
Justinian I: Byzantine Emperor (527-565), nephew and successor of Justin I. One of his first acts was to reform the tax system and recode Theodosius’ laws. He was personally involved in religious conflicts and convened the 5th Ecumenical Council (553). Justinian considered himself primarily an orthodox emperor and took harsh measures against the remaining pagans. Many of his political and fiscal actions provoked strong reactions on the part of the senate and the factions and led to the Nika Riots. Justinian instigated numerous building projects, erecting approximately 30 churches in Constantinople, including the famous church of Agia Sophia. Regarding foreign policy, he successfully confronted the Persians and the Vandals in the East and focused on the recovery of the West. This he temporarily achieved, but at such cost that the Empire was left exhausted; the barbarians in the Balkans plundered the Greek peninsula as far as the Isthmus and barbarian tribes settled at the borders. His military operations exhausted Byzantium financially and militarily and had no real effect, as Italy and other areas he conquered were soon lost again. After his death, the weakened empire had to face new attacks, culminating in the Arab conquests, which negated the majority of Justinian’s conquests beyond the borders.
The monastery of Agios Stephanos: Access to the Monastery of Agios Stephanos (St. Stephen) is gained via a small stone bridge leading from the modern road to the main entrance. Although the first evidence of habitation on the rock dates back to the 12th century, the monastery was founded in the 14th century by Anthony, a member of the Catacuzenus dynasty. In the mid 16th century the catholicon was restored by Philotheos, the monk who is regarded as the second founder. In 1545 Patriarch Jeremiah I declared Agios Stephanos independent and stavropegic, privileges which it retained for the following 200 years. The new catholicon dedicated to Agios Charalambos was built in the late 18th century. Apart from the old and new catholica and a few later buildings, a number of other structures have been restored and preserved: the oblong refectory, which is roofed over by two elliptical domes and presently functions as a sacristy - cum - museum, a small square vaulted kitchen, stables and cells. The old catholicon is composed of the lite and the church proper. A tripartite arched opening in the square lite leads to a single nave timber-roofed church ending in a three-sided apse to the east. The wall paintings in Agios Stephanos were completed in two phases. The first, which would appear to have been sponsored by Abbot Metrophanus and Brother Gregory, accounted for the paintings in the sanctuary, the nave and the greater part of the lite. These follow the anti-classical tradition of post-Byzantine art and, based on stylistic features, date to the 1st half of the 17th century; they have been attributed to artists from Linotopi in Epirus. The paintings covering the west wall in the lite and the lower zone on the piers of the tribelon leading to the nave both derive from the second decoration phase, and were sponsored by Abbot Grigorios. Built in 1798, the new catholicon is a cross-in-square triconch domed church dedicated to Agios Haralambos. The Prothesis and Diakonicon also have domes, while to the east the church ends in three semicircular apses.
The church of Agioi Anargyroi: The church of Agioi Anargyroi (the Unmercenary Saints) stands on the steep hillside on the north side of the city of Kastoria. It is a three-aisled basilica with narthex, which initially had a triple vaulted roof dating to the 10th -11th century. On the inside the naves are separated by walls punctuated by asymmetric arched openings. The central nave is wider and higher than the other two, ending in a semicircular conch to the east. The conches of the side naves are the same shape but smaller. The church is illuminated by a few double light windows in the upper wall of the central nave - two on each of the long sides, and one in each of the short sides (east and west). The masonry consists of irregular stones alternating with red tiles arranged in patterns (diamonds, suns, trees and dogtooth courses). These are combined with mortar to create an aesthetically pleasing effect.Agioi Anargyroi is the only church in Kastoria to have sculpture decoration, featuring carved rosettes, crosses, animals and stars in circles. Inside the church there are also sections of the marble templon assembled during restoration work.The interior is decorated with successive layers of exquisite wall paintings. The scenes in the first layer, dating to around 1000 AD, are mainly visible on parts of the narthex, where earlier interventions brought to light depictions of Saints Basil and Nicholas, Saints Constantine and Helena, and the figure of the deceased Constantine. These representations are characterized by intensely outlined faces, linear characteristics, a limited number of colours for rendering figures and a lack of volume.The second layer wall paintings date to the second half of the 12th century. According to inscriptions in various parts of the church and the dedicatory representation in the north nave, they were sponsored by Theodore Lemniotes and his wife Anna Radene, who renovated the church and dedicated it to Agioi Anargyroi (the Unmercenary Saints), calling on them to intercede for their personal health. Information from the founders’ mural and another scene in the south nave reveal that they took monastic vows - Theodore Lemniotes took the name brother Theophilus Lemnos.The iconographic programme in the second layer features scenes from Dodecaorton and the Passion of Christ in the nave, the Eucharist in the sanctuary, and the lives and martyrdoms of saints in the side naves. Marked differences in style suggest that two artists with differing concepts of art worked in the nave. In the first case the saints are rendered in a hieratic stance, stern of expression, with oval faces, large round eyes and arched eyebrows. The garments are rich, painted in a variety of colours, with folds that follow the movements of the body. This painter’s depictions are representative of “dynamic Comnenian style” and recall the art in Agios Georgios at Kourbinovo. In contrast, the slightly earlier figures attributed to the second artist are rigid and expressionless, with linear faces and clothing folds. The main figures appear disproportionately larger than the minor ones, and the scenes are almost entirely devoid of any surrounding detail (buildings or landscape). A third artist painted the surfaces of the narthex in the monumental tradition of late Comnenian painting. The exterior murals on the west facade date to the same period. They depict the Supplication, the Apostles, the Unmercenary Saints and St. Nicholas.
Pechenegs: Central Asian tribe of Turkish origin. In Greek sources they are variously known as Patsinakes, Patzinakes and Pechenegs. In the 5th century they moved into west Asia and south Russia, while in the 9th century they settled on the banks of the lower Danube. The Byzantines developed good relations with them and used them against the Bulgarians. Later they became very dangerous for Byzantium, particularly in the 11th century, when they moved south of the Danube and reached as far as Adrianople. The last battle between the Byzantines and the Pechenegs is reported in 1091: they were routed, and the few survivors merged with the Bulgarians.
Samuel: Tsar of the Bulgarians from 996/7 to 1041. Youngest son of Count Nicholas, governor of western Macedonia, he was one of the most distinguished figures of medieval Bulgaria. Samuel initially ruled along with his three brothers, but following their death in 996/7 he became sole ruler of the Bulgarians. He re-established the Bulgarian Patriarchate in Ohrid and waged continuous wars against Byzantium. In 981 he invaded the northern frontier of the empire and marched south into Greece, occupying several towns. His victorious march came to an end in 996 when he was defeated on the banks of the Sperchios River by the Byzantine army. Emperor Basil II started a new cycle of repeated attacks in 1000, which led to the depletion of the Bulgarian army, ending in total defeat at the Battle of Kleidi in 1014.
Bohemund: Prince of Taranto and Antioch, eldest son of the famous Viking leader Robert Guiscard. In the Norman attack on Byzantium his army got as far as Larissa, where it was beaten back by Alexius Comnenus. During the First Crusade he captured Antioch and briefly served as prince of the city. Bohemund married Constance, daughter of King Philip I of France, with whom he had a son. He died in 1111.
Alexius I Comnenus: Emperor of Byzantium from 1081 to 1118, founder of the Comnenian dynasty. Son of John Comnenus and Anna Dalassene, he was originally a general in the imperial army. Using this position he led a revolt supported by the army and the aristocracy, which ended in the capture of Constantinople and his ascension to the imperial throne on 1 April 1081. The empire Alexius inherited was at a very critical juncture: the aristocracy were in revolt, the Seljuks had taken over much of Asia Minor and the capital and the Danubian provinces were under attack. The raids continued at greater or lesser intensity over several years. To address these difficulties, Alexius turned to the West, and signed peace treaties with the Venetians and the Germans. With regard to domestic affairs, he attempted to reform and revitalize the economy and trade so as to stop deflation of the Byzantine currency, and overhauled the administration. The first Crusade took place during his reign. Alexius exercised diplomacy in dealing with the waves of crusaders, providing them with vessels to cross over to Asia Minor. After extensive negotiations, the crusader leaders agreed to hand back any lands they might capture that had previously belonged to the Byzantine Empire. However, Alexius failed to prevent them capture Antioch and Jerusalem. He died in 1118.