Markeli
Medieval Byzantine and Bulgarian frontier stronghold, site of two major battles.
Markeli (Маркели in Bulgarian, Μαρκέλλαι in Greek, and Marcellae in Latin) was a fortress on the medieval border between Byzantium and Bulgaria. Its ruins sit in Karnobat Municipality, Burgas Province, in southeastern Bulgaria, about 7.5 kilometers from the modern town of Karnobat. Built in Late Antiquity, it saw two major medieval battles: the Battle of Marcellae in 756 and another in 792.
The stronghold became strategically important in the late 7th century, when the First Bulgarian Empire’s rise and expansion turned it into a key frontier post just south of the Balkan Mountains. Control shifted between Bulgarians and Byzantines, each using it as a launchpad for campaigns north or south. Markeli first came under Bulgarian rule in 705, when Justinian II ceded it—along with the entire Zagore region—to Bulgaria.
In 756, Byzantine Emperor Constantine V launched a campaign against Bulgaria. The year before, Bulgarian forces under Kormisosh had raided Byzantine Thrace and reached Constantinople, but by 756 Vineh was on the Bulgarian throne. Constantine V’s army advanced into Thrace and clashed with Bulgarian troops at Markeli, then a border fortress. The Byzantines won, and to stave off further invasion, Vineh sent hostages to Constantinople.
In 792, Markeli was again the scene of a major clash. This second battle came during a prolonged period of aggression between the two powers, with Bulgarian ruler Kardam and Byzantine Emperor Constantine VI each having invaded the other’s territory in recent years. Byzantine strategic mistakes led to a heavy defeat. The Bulgarians killed several of the emperor’s personal servants and prominent generals, and captured his tent, treasury, and horses.
In 811, Nikephoros I Logothetes’s forces set out from Markeli on their doomed invasion of Bulgaria, which ended with the emperor’s death at the Battle of Pliska. Byzantine scholar Anna Komnene records that in 1089, her father Alexios I Komnenos had conflicts and negotiations with Pechenegs and Cumans who had camped at Markeli. The fortress remained manned and inhabited until sometime in the 12th century.
Markeli lies south of the Balkan Mountains near the Mochuritsa River, a major tributary of the Tundzha, where the river leaves the Karnobat Valley at the western tip of the Hisar Heights. Its location was chosen to guard the Rish and Varbitsa mountain passes.
- Location
- Karnobat Municipality, Burgas Province, southeastern Bulgaria
- Type
- Frontier stronghold
- Period
- Late Antiquity to 12th century
- Notable events
- Battle of Marcellae (756), Battle of Marcellae (792)
- Area
- 173 acres (0.70 km²)
- Excavation started
- 1986
Lore & Background
Markeli acquired its strategic importance in the late 7th century, when the establishment of the First Bulgarian Empire and its expansion turned it into a vital frontier stronghold just south of the Balkan Mountains. It would often change hands between Bulgarians and Byzantines, who would use it as a favourable starting point for military campaigns southwards and northwards respectively. Markeli first came under Bulgarian rule in 705, when it, together with the whole region of Zagore, was ceded to Bulgaria by Justinian II.
In 756, Byzantine Emperor Constantine V organized a campaign against Bulgaria. The previous year, Bulgarian forces under Kormisosh had plundered Byzantine Thrace and reached the capital Constantinople, though by 756 the Bulgarian throne was occupied by Vineh. Constantine V's army advanced into Thrace and was engaged by Bulgarian forces at Markeli, which at the time was a border fortress. The Byzantines came out victorious in the skirmish, and to prevent a further invasion, the Bulgarian ruler Vineh had to send hostages to Constantinople.
In 792, Markeli was once more in the centre of a major Byzantine–Bulgarian conflict. The second battle of Marcellae came during a long period of aggression between Byzantium and Bulgaria, with Bulgarian ruler Kardam and Byzantine Emperor Constantine VI each invading foreign territory in the past few years. Due to strategic errors, the Byzantines suffered a heavy blow in this battle. Some of the emperor's personal servants and eminent strategoi were killed by the Bulgarians, who also captured the emperor's tent, treasury and horses.
Reader's Guide
Markeli's significance lies in its role as a strategic frontier stronghold that witnessed pivotal Byzantine–Bulgarian conflicts. Its location south of the Balkan Mountains, defending the Rish and Varbitsa mountain passes, made it a key military asset for both empires. The two battles fought there—in 756 and 792—reflect the shifting power dynamics between Byzantium and the First Bulgarian Empire. The fortress also served as a launching point for Nikephoros I Logothetes's ill-fated invasion of Bulgaria in 811, which ended in his death at the Battle of Pliska. Later, in 1089, Byzantine scholar Anna Komnene records that her father Alexios I Komnenos had conflicts and negotiations with the Pechenegs and Cumans who had pitched their tents at Markeli. Archaeological research since 1986 has revealed that the castle was built in Late Antiquity, with fortifications dating to the reign of either Anastasius I or Justinian I. The ruins include a Christian basilica, a well tower, and an ancient bridge, indicating a well-planned defensive and residential complex that was manned until some time in the 12th century.
Did You Know?
- The fortress's ramparts were up to 10 metres high and had over 3-metre ditches before them.
- In 811, Nikephoros I Logothetes's forces departed from Markeli in their invasion of Bulgaria, which ended with his death at the Battle of Pliska.
- The entire fortress, including embankments dating to the early 9th century, had an area of 173 acres.
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