Fortresses, Sieges and Peace

Fortifications in the Bulgarian lands differed greatly in size and purpose. Small forts offered temporary refuge to people from nearby settlements, but advancing armies often captured them quickly or simply bypassed them. The great fortified cities—Tarnovo, Bdin, Sredets, Plovdiv, Varna, Kaliakra, Lovech, Cherven, Mesembria, and Ovech—were another matter. Their walls, garrisons, storehouses, and water supplies allowed prolonged resistance. Because failure was dangerous, medieval commanders avoided unnecessary sieges, yet the fall of a key city could decide an entire war.

To make a blockade effective, attackers had to close every exit and prevent an outside army from relieving the garrison. This was difficult when a fortress stood among cliffs and broken ground, so the main forces often concentrated on guarding the gates. The besieged stockpiled food and filled their cisterns in advance. They erected multi-storey wooden structures on the towers and covered them with raw hides or bundles of vine branches to resist fire and stone impacts. From projecting platforms they dropped heavy stones tied to ropes or chains, then hauled them back up for repeated use.

The simplest attacks were directed against weak sections of the wall. Soldiers worked with picks, levers, and axes; Byzantine narratives sometimes add swords, although these were poorly suited to such labour. Sappers dug tunnels beneath the foundations. At Adrianople in 1205, Latin miners removed the earth secretly and supported their passage with dry wooden props. Kaloyan later attempted the same approach without success, while defenders commonly searched for a mine by digging counter-tunnels. Assault ladders were made from elm or ash. Sections up to about four metres long were assembled beside the wall and ended in hooks. Climbing them beneath stones, arrows, and heated resin required exceptional courage.

The crossbow became an especially important siege weapon after its introduction by western crusaders in the late twelfth century. Bulgarian sources use the terms samostrel and tsagra, probably for manually and mechanically spanned varieties. With the first type, the archer used his foot and a hook attached to his belt; with the second, a geared mechanism and crank drew back the string. Part of such a mechanism has been found at Tsarevets. The short bolts had much heavier heads than ordinary arrows and could pierce forged armour. A mechanical crossbow had a range of roughly two hundred paces and was accurate but slow: while an experienced bowman could loose about ten arrows a minute, a crossbowman managed only one or two bolts. Strings made from ox sinew lost their elasticity in damp weather.

Stone-throwing engines bombarded fortifications with carefully shaped stone projectiles. Chroniclers exaggerated when they described entire rocks and hills being hurled, but the machines were genuinely destructive, and the largest were credited with ranges exceeding a thousand paces. During the siege of Serres, Kaloyan placed an enormous stone-thrower on high ground opposite the citadel and forced its defenders to surrender. Mobile siege towers were built by skilled engineers with several storeys, covered with fresh hides against fire, and moved on wheels or rollers. The upper level carried a drawbridge, while the lowest sometimes contained a battering ram—a swinging beam with an iron head used to break and loosen masonry.

The siege of Plovdiv in 1323 demonstrates both the potential and the uncertainty of these machines. Andronikos III besieged the city for four months against a garrison of one thousand horsemen and twice as many armoured infantrymen. A German engineer built a five-storey tower with sixteen wheels. One hundred men pushed it from inside, while its floors held a total of forty soldiers with mechanical crossbows. The machine approached the wall to the sound of trumpets, but passed over a forgotten ancient cistern. Its covering collapsed beneath the weight and the tower fell in. None of the men inside was killed, but the siege was abandoned soon afterwards.

Kaloyan’s campaigns provide the fullest evidence for siege warfare in the early thirteenth century. At Varna, the Bulgarians filled the city ditch and moved a great tower across the embankment until its bridge reached the battlements; the formidable fortress was captured in three days. At Didymoteicho in February 1206, stone-throwers destroyed sections of the walls and several towers, but dismounted heavy cavalry failed to break into the city. Niketas Choniates also reports an attempt to divert the Maritsa. The scale of such a project has caused doubts, and the more likely objective was to cut the channels supplying water. Kaloyan withdrew after seventy days. In the following year, thirty-three stone-throwers worked day and night outside Adrianople. The garrison blocked two breaches with timber and refuse, then set the barricades alight during the attack. Summer heat and the departure of the Cuman allies brought the siege to an end.

Defence did not mean waiting passively. At Prosek in 1199, Dobromir Chrysos resisted Alexios III Angelos from a fortress protected by steep cliffs. A skilled engineer directed stone-throwers from the high towers; even shots that missed shattered against the rocks and showered the attackers with sharp fragments. During the night, a Bulgarian detachment came out, burned the enemy engines, and drove away the forward guard. After this success, the people inside drank wine, mocked the besiegers, and rolled empty barrels down the slope. The crashing noise in the darkness created the impression of another attack and unsettled the Byzantine camp. The emperor opened negotiations the next day.

Gunpowder weapons appeared on the Bulgarian coast in the second half of the fourteenth century, but they were still rare. In 1366, the ships of Amadeus of Savoy bombarded Nesebar with bombards mounted in the bows of Genoese vessels. In Old Bulgarian such guns were called trabachi, probably from the word for a tube or pipe. Early bombards could not easily demolish thick walls, so their shots were mainly directed into the town to create fear. The Savoyard account states that the Bulgarians “fought well”; their lack of panic suggests, without proving, that guns were no longer wholly unfamiliar.

Several prolonged sieges changed Bulgarian history. Isaac II Angelos’s three-month failure before Lovech contributed to a peace by which Byzantium recognized the restored Bulgarian state. In 1393, Bayezid I surrounded Tarnovo with an army assembled from the Balkans and Asia Minor. Gregory Tsamblak describes a complete and lengthy blockade rather than a brief assault. Later local traditions speak of treason and a small gate through which the Ottomans entered Tsarevets, but this has not been securely established. Tsamblak himself explains the fall through divine will and the “triumph of sin.” His narrative does not support the idea that the walls were taken by a successful open assault; the capital more probably capitulated after exhausting its means of resistance.

War was usually followed by a dispute over the terms of peace. The victor demanded lands, fortresses, titles, or political recognition, but the defeated side rarely accepted everything without objection. In 1195, Alexios III Angelos sent envoys to Peter IV and Ivan Asen I, but the Bulgarian demands were rejected as unacceptable and humiliating. Their exact content is unknown; they probably concerned royal or imperial recognition as well as territory. In 1307, Theodore Svetoslav secured recognition of his conquests. After his victory at Rusokastro, Ivan Alexander likewise dictated more favourable terms. John Kantakouzenos presents the resulting treaty as mutually beneficial, but his account conceals the pressure under which Andronikos III was acting.

Hostages, called talnitsi in medieval Bulgarian, served as living guarantees that treaties would be observed. They were generally held in honourable captivity, but their freedom depended on relations between the two states. Under the Peace of Lovech in 1187, the young Kaloyan was sent to Constantinople. He remained there for about two years before escaping. Warfare between Bulgarians and Byzantines intensified again after his flight. The surrender of a member of the ruling family reveals how little trust existed even after a peace had been solemnly concluded.

Negotiations were also governed by ideas of rank. In 1328, Andronikos III offered concessions to Michael Shishman if the Bulgarian ruler acknowledged the supremacy of the Byzantine basileus and called himself his slave. Michael answered that one emperor could not submit to another. In ceremonial practice, however, Bulgarian rulers showed respect for the Byzantine court: meetings with the emperor usually took place on Byzantine territory. Michael Shishman and Andronikos III once negotiated for eight days, and on another occasion spoke without dismounting. Ivan Asen II remained at Gallipoli while his family crossed into the lands of John Doukas Vatatzes, probably because Nicaean law barred foreign rulers from entering the empire. The ceremonial relationship with Serbia was reversed: Kings Stefan Vladislav I and Stefan Uroš II Milutin visited Tarnovo, thereby acknowledging the higher rank claimed by the Bulgarian emperor.

The practical work was performed by envoys, interpreters, and trusted treaty specialists. Documents were prepared in both languages, and differences between the versions had to be carefully eliminated. George Akropolites shows how specialized this work had become in his account of the Peace of Regina in 1256. The Bulgarian plenipotentiary was Rostislav Mikhailovich, the father-in-law of Michael II Asen. Theodore II Laskaris welcomed him with horses, gold-woven clothing, and an immense quantity of valuables. Rostislav then accepted a treaty that ceded extensive territories around Skopje, Priština, Prizren, and Velbazhd to the Byzantines, together with positions in the Rhodopes, while the Bulgarians had to evacuate Tsepina. The peace caused intense resentment, and the resulting political crisis ultimately cost Michael II Asen his throne.

A treaty took effect only after the oath had been sworn. Before Rusokastro, Ivan Alexander and Andronikos III had already agreed on peace, but had not yet pronounced the oath. After receiving reinforcements during the night, the Bulgarian ruler attacked the following morning, without Byzantine writers formally accusing him of perjury. Breaking an oath already taken was nevertheless regarded as a grave sin. Alexios III Angelos lured Ivanko to a meeting with a promise of safety confirmed over the Scriptures, then arrested him. By contrast, when Theodore Komnenos Doukas invaded Bulgaria in 1230 despite his treaty with Ivan Asen II, the Bulgarian ruler displayed Theodore’s written oath on a standard before the Battle of Klokotnitsa. In 1328, Michael Shishman offered Andronikos III a miracle-working iron cross as a pledge of his fidelity.

A dynastic marriage was considered a firmer foundation for peace than a simple promise. At least five Bulgarian-Byzantine agreements provided for a Bulgarian ruler to marry a Byzantine princess. The results were not always lasting. Constantine Asen married Maria Palaiologina, a niece of Michael VIII Palaiologos, after Mesembria and Anchialos were promised as her dowry. The emperor delayed and ultimately failed to fulfil the condition even after the birth of an heir. Michael Shishman’s marriage to the Serbian princess Anna Neda likewise failed to prevent war. After their divorce, she and her sons were exiled, worsening relations with Stefan Uroš III Dečanski. Following the Bulgarian defeat at Velbazhd, the Serbian king placed Ivan Stefan, the son of Michael and Anna Neda, on the Bulgarian throne.

Other marriages sustained relations with the Serbian court. An unnamed daughter of Ivan Asen II, Anna Terter—the daughter of George Terter I—and Elena, the sister of Ivan Alexander, married rulers of the Nemanjić dynasty. These unions were intended to guarantee peace between the two states, but the princesses retained political influence of their own. Elena was said to lead a “Bulgarian” court faction in Serbia, although the exact nature and strength of this group remain uncertain.

Under Boril, dynastic diplomacy reached an unusual intensity. Around 1213, the Latin barons persuaded Emperor Henry to marry Maria, the daughter of Kaloyan and Boril’s stepdaughter. Boril himself married one of Henry’s nieces, while in 1214 a marriage was discussed between a daughter of the Bulgarian ruler and the Hungarian heir Béla. These projects outlined a possible alliance between Bulgaria, the Latin Empire, and Hungary. It did not develop after Henry’s death in 1216. One obscure report accuses Maria of poisoning her husband, but there is too little evidence either to accept the accusation or to connect it confidently with international politics.

In the late thirteenth century, Tatar pressure imposed marriages and hostage arrangements that the Tarnovo court would hardly have accepted under other circumstances. A daughter of George Terter I was married to Chaka, the son of Nogai, while Theodore Svetoslav was later sent as a hostage to the Tatar camp. This followed earlier diplomatic miscalculations. Constantine Asen joined the distant coalition of Charles I of Anjou against Constantinople, while Michael VIII Palaiologos won over the nearby Tatars through money and the union of his illegitimate daughter Euphrosyne with Nogai. The Tatar campaign of 1273 opened a period of severe dependence for Bulgaria. Equally unrealistic was the mission sent by Queen Maria Palaiologina to the Egyptian sultan with a proposal for a joint attack on Constantinople. The sultan knew little of distant Bulgaria and dismissed the envoys without result.

The Ottoman threat gave dynastic alliances a new purpose. The peace of 1355 provided for Keratsa-Maria, the daughter of Ivan Alexander, to marry Andronikos IV Palaiologos. Because both were children, special ecclesiastical permission was required; the union was presented as a common defence of Bulgarians and Byzantines against the Turks, but it did not produce lasting military unity. Around the mid-1370s, Kera Tamara was given in marriage to Murad I. The union probably moderated Ottoman policy towards the Tarnovo Tsardom for a time. Ottoman chronicles describe Ivan Shishman appearing before the sultan with his family and dressed in a white burial shroud, pleading to retain his throne. Kera Tamara’s influence may explain the mercy shown, but this remains a hypothesis.

Diplomats and rulers repeatedly promised a “firm and eternal peace,” although treaties served immediate interests and were often broken when circumstances changed. Gifts, marriages, and solemn oaths might buy time, but they did not remove rivalry. For ordinary people, peace had a far more direct meaning: a secure harvest, homes left unburned, open roads, and life without flight behind fortress walls. This is why prophetic writings filled with forecasts of war and bloodshed also preserve the brief hope that “there will be peace in the land of the Bulgarians.”