The history of Bosnia in the high middle ages is frequently confused and confusing. But three powerful rulers stand out: Ban Kulin (who ruled from 1180 to 1204), Ban Stephen Kotromanić (1322-1353) and King Stephen Tvrtko I 1353-1391). Under the second of these, Bosnia expanded to include the principality of Hum (what is today known as Herzegovina); and under the third it expanded further to the south and also acquiring a large part of the Dalmatian coast. Indeed, during the second half of Tvrtko's reign Bosnia was the most powerful state within western Balkans.
During that time Hungary was a dominant neighboring country under whose rule was Croatia but not Bosnia.
The map of Balkan and Europe
In the 13th and early 14th century Serbian Kingdom also grew into militarily powerful state; but there was newer any large scale attempt by Serbian kings to conquer Bosnia . As the kings of Hungary were frequently to discover, the impenetrability of Bosnian terrain made it a troublesome prize to obtain, and its fractious noble landowners made it, ones obtained, an asset of dubious value.
Most puzzling feature of Bosnian medieval history was the schismatic Bosnian Church. This Church seem to have fallen away from the Catholic Church in the 13th century, and to have operated on its own in Bosnia until the coming of Franciscans, who tried to reassert the authority of Rome in the 1340s. There after Bosnian church competed against Roman Catholic Church for a century, until its functionaries were either expelled or forcibly converted to Catholicism on the eve of Turkish conquest. Throughout the lifetime of the Bosnian Church, papal writers accused the Bosnians of heresy.
Ban Kulin had legendary status on both medieval and modern Bosnia. Te reason for this is because he brought prosperity and peace o Bosnia. During 24 years of peace Ban Kulin economically developed Bosnia by making commercial treaty with Ragusa (Republic of Dubrovnik) in 1189, and encouraged Ragusan merchants to exploit rich Bosnian mines , he also established good relations both with the ruler of Hum (today known as Herzegovina), who married Kulin's sister and with the Serbian grand župan, Stephen Nemanja, founder of the Nemanjid dynasty which was to turn Serbia into great power during the next two centuries.
However relations with Hungary were less amicable with two other states; Hungary, which was still regarded itself as holding ultimate sovereignty over Bosnia, and Zeta (modern Montenegro), which allied it self with Hungary for tactical political reasons.
Church politics, not war, was the form the conflict took. Bosnia (unlike Orthodox Hum) was Catholic country, and came under the authority of the Archbishop of Ragusa (Dubrovnik), because of its remoteness Bosnia was little interfered by Ragusan hierarchy: it was virtually allowed to appoint its own bishop (whose diocese extended northwards into Hungarian-Croatian lands). Hungary wanted closer control over the Bosnian bishoprics, and campaigned at Rome in the early 1190s to have it transferred to jurisdiction of more pro-Hungarian Archbishop of Split. Then ruler of Zeta (modern Montenegro), who was keen to discredit both Bosnia and Ragusa, started sending letters to the Pope complaining that Ban Kulin, his wife and thousands of his subjects had become heretics, these complains may have been a way of requesting papal permission to invade some Bosnian territory. But this was defused by Ban Kulin by holding a council of the Bosnian Catholic Church at Bilino Polje in 1203 where a series of errors were officially renounced. These errors seem to have related to lax religious practices rather then any serious doctrinal heresies; but the tradition of stigmatizing Bosnia with accusations of heresies had now been established.
During the half-century which followed, Bosnia was under constant pressure from its more powerful Hungarian neighbor. Hungarians had not given up their plan to gain control over the bishopric of Bosnia. The papacy sent a constant stream of requests to the Hungarian rulers and bishops during the 1230s to drive out heresy from the diocese of Bosnia.
Hungarian rulers wanted a religious justification for invasion of Bosnia. The invasion duly took place in the latter 1230s; by 1238 the Hungarians had captured the south central region of Bosnia and were busy attempting to install the Dominican order of friars. The Bosnian Ban, Ninoslav, retained some territory, however; and when the Hungarian army was suddenly withdrawn northwards in 1241 to meet the threat of Mongol invasion of Hungary he was able to retain power in Bosnia. The Mongols crushed the Hungarian army, and proceeded on trail of plunder and destruction trough northern Croatia to Dalmatia. But on hearing of the death of the Great Khan they returned eastwards, via Zeta (Montenegro) and Serbia. They thus managed to circumnavigate Bosnia, leaving it largely unscathed.
In the second half of 13th century Bosnia seems to have led a more isolated existence. Hungary persuaded the Pope in 1252 to place the bishopric of Bosnia under the authority of an archbishopric inside Hungary; however; the main effect of this was that henceforth the Bosnian bishop lived outside Bosnia (in Hungarian-controlled Slavonia), and the leverage which any outside authority could exert over the Catholic Church inside of Bosnia was reduced almost to nothing . Hungary made one more attempt to invade Bosnia in 1253, but there after the original Banate of Bosnia - the successor to Ban Kulin's state - seem to been left to its own devices for the rest of the century. Several northern regions of modern Bosnia, however, such as Soil or 'salt' region round Tuzla, were assigned to members of the Hungarian royal family. The north-eastern section of these lands was combined with territory in northern Serbia to form a Hungarian duchy known as Mačva .
It was from these northern lands that the next ruling family of Bosnia emerged. Stephen Kotroman succeeded his father in the 1280s as a ruler of one of the northern Bosnian territories, and married the daughter of the ruler of Mačva. He then conducted a prolonged struggle for power, the details of which are unclear, against another noble family, the Šubićes, based in the Bribir region of Dalmatia. The Šubićes appeared to have ruled the old Banate of Bosnia for the most of the two decades of the 14th century, and to have friendly relations with Kotroman's son, Stephen Kotromanić, for some of the time. But in the early 1320s Kotromanić gained the upper hand: a Šubić was a Ban of Bosnia in 1318, but Kotromanić had replaced him by 1322. Once in power, he began building up a large Bosnian state which united the old Banate with some northern territories. To this he added by conquest, areas to the west of Banate which have previously been part of Croatia and would henceforth remain as Bosnian territory. He further extended this conquest to take couple of hundred miles of Dalmatian coast between Ragusa and Split. In 1326 he annexed most of the Hum (Herzegovina), thus making a single political entity of Bosnia and Herzegovina for the first time. Until then Hitherto Hum had existed under its own succession of local ruling families; and its religious history had been separate too, with large Orthodox population .
Bosnian royal family Kotromanić
Kotromanić took care to cultivate friendly relations with foreign powers. It was his great good fortune that that Serbian kingdom, which was undergoing an extraordinary growth in power under its ruler Stephan Dušan, was preoccupied with expanding southwards into Macedonia, Albania and northern Greece. Kotromanić signed treaties with Ragusa (1334) and Venice (1335), and cooperated willingly with the Hungarian king, sending Bosnian troops to assist him in his campaigns against troublesome nobles in Croatia. When Stephen Kotromanić died 1353, he left behind a Bosnian state which was independent, prosperous and powerful.
But the Bosnian stability still depended on the cooperation of noble families who had their own power-basis in the different parts of the country. The nephew who succeeded Kotromanić, Stephen Tvrtko, was only aged 15, and did not have the authority or the military power to keep these centrifugal forces together. At the same time the Hungarian king was keen to exploit divisions in Bosnia in order to regain territories for him self. For the first 14 years of his reign Tvrtko had to contend with Bosnian revolts and seizures of land by Hungary; in 1366 he was even forced to seek refuge at the Hungarian court, when a group of Bosnian nobles set up his brother Vuk in his place. But by 1367 - apparently with the assistance of the King of Hungary, who realized that he had been stirring up troubles from which neither Tvrtko nor him self would benefit - Tvrtko was back in power in Bosnia. Thereafter he had little troubles from Hungarian king, who become more concerned with the events on Hungary's northern borders.
Tvrtko now turned his attention southwards. The huge Serb empire had broken up very quickly after the death of its creator, Stephen Dušan, in 1355. One of the Serbian noblemen who were now trying to cave out territory from its remains was Lazar Hrebljanović, who was engaged in a complex struggle for power with other nobles in the region of south-western Serbia, Hum (Herzegovina) and Zeta (Montenegro). Tvrtko gave Lazar the assistance he needed, and was rewarded in the subsequent share-out of the spoils with a large strip of territory adjoining Bosnia to the south and south-east: parts of Hum, Zeta and southern Dalmatia (including a section of the coast between the Ragusa and the Bay of Kotor) and what later became the Sandžak of Novi Pazar. This last component included the monastery of Miloševo, which contained the relics of the Saint Sava, one of the most sacred figures in the history of the Serbian Orthodox Church.
King Stephen Tvrtko I Kotromanić of Bosnia
In 1377 Tvrtko celebrated this improvement in his position by having him self crowned as King at Miloševo - not only King of Bosnia but King of Serbia too. King Tvrtko never seriously attempted to exercise political power over Serbia . King Tvrtko's political and territorial ambitions lay elsewhere. He tried to set up a port of his own on the northern side of the Bay of Kotor: he called it Novi meaning 'new' (modern Herceg-Novi), but this plan was quietly dropped because it angered the Ragusans. Meanwhile a civil war has broken out in the Croatian lands after the death of the King of Hungary in 1382. Aligning himself with one of the most powerful of competing Croatian families, Tvrtko sent his troops into Dalmatia and took control of the entire coastline (including even son of the islands), with the exception of the Ragusa, which retained its independence and Zadar which was under Venetian suzerainty. Venice had strong ambitions in this region, and would eventually regain most of the Dalmatian coast after Tvrtko's death. But for the time being Tvrtko was the master of a greatly expanded Bosnian kingdom which had also taken in parts of northern Croatia and Slavonia: in the last two years before his death in 1391 King Tvrtko was calling himself King of Croatia and Dalmatia too.
With the late 1380s and early 1390s we have reached another of the great turning-points in western Balkan history. Ottoman Turkish armies had been moving westwards across Thrace and Bulgaria since the 1350s, and in 1371 a large a large contingent of Serbian forces had met them in Bulgaria, and have been heavily defeated. In the 1380s the Turks have began raiding Serbia itself; and in 1388 a Turkish raiding party crossed into Bosnian-ruled Hum (Herzegovina), where it was wiped out buy forces commanded by a local nobleman, Vlatko Vuković. In 1389 Tvrtko's old Serbian ally Lazar (who had modestly taken the title 'Prince' when Tvrtko had proclaimed himself King) refused to accept the Turkish suzerainty, and called his neighbors and allays to help. King Tvrtko sent large Bosnian force under Vlatko Vuković, which fought along side Prince Lazar's army at the battle of Kosovo Polje in June 1389. Though Serbian myth and poetry have presented this battle as a cataclysmic defeat in which the flower of Balkans chivalry perished on the field and the Turks swept on trough the rest of the Serbia, the truth is a little less dramatic. Losses were heavy on both sides, and the Prince Lazar was captured and executed; but the remains of both sides withdrew after the battle, and for a while the Serb and Bosnian forces have believed that they have won. It was not the battle itself which brought about the fall of Serbia to the Turks, but the fact that while the Serbs had needed all of the forces they could master to hold the Turks to an expensive and temporary draw, the Turks were able to return, year after year, in ever increasing strength. By 1392 all the Serbian Orthodox lands, apart from Bosnian-ruled Hum, have submitted to Ottoman suzerainty.
King Tvrtko's gold coin
After Tvrtko's death in 1391 Bosnia entered long period of weak rule and political confusion. One account of Bosnia written by the French pilgrim Gilles Le Bouvier, paints a miserable picture of the place: 'They live purely on wild beasts, fish from the rivers, figs and honey, of which they have sufficient supply, and they go in gangs from forest to forest to rob people who are traveling from one country to another.
The Bosnia state did not split up after Tvrtko's death, as it had after the death of Stephen Kotromanić, but nobleman with strong regional power-bases reasserted themselves, and the rulers of Bosnia were at the mercy of shifting patterns of rivalry among the leading noble families. The Hungarian king also took an interest again in Bosnian affairs, though heavy defeat of the Hungarian army by the Turks in 1396 limited Hungary's capacity to intervene militarily in Bosnia for several years. In 1404, however, when the Bosnian King Ostoja was driven out by the nobles and replaced by an illegitimate son of King Tvrtko (Tvrtko II), he returned with a Hungarian army and reconquered part of the country. Over next 10 years, with Hungarian backing, Ostoja reasserted his rule and helped to mend relations between Hungary and the most powerful of the Bosnian nobleman, Hrvoje.
Then, in 1414, a new factor entered to disrupt the balance of power, both militarily and politically: the Ottoman Turks proclaimed the exiled Tvrtko II as rightful King of Bosnia, and sent a large raiding force into Bosnian territory. When a much larger Turkish army returned to Bosnia in the following year, there was a new alignment of forces: on one side King Ostoja and Hungarian army, and on the other side the Turks and the Bosnian nobleman Hrvoje. The Hungarian army was heavily defeated in central Bosnia, and although Ostoja made some sort of a deal in which it was agreed that he, not Tvrtko II, would be confirmed as a King, it was clear that from now on Ottoman Empire would have influence rivaling that of Hungary over Bosnian affairs.
With the eventual Turkish conquest of Bosnia in mind, some modern historians, especially Serbian ones, have felt instinctively hostile towards those Bosnian rulers and nobleman who have collaborated in this way with the Turks. But their actions were no different from those of previous players in the Bosnian political game who have appealed to Hungary for support; the main difference in their minds would probably have been that the Turks seemed a more remote and perhaps ephemeral presence, less likely to impose any kind of direct rule.
Ostoja held power for few more years, and actually enlarged the territory he controlled. But after his death in 1418 his son faced the same problems of competing noble families and Turkish intervention. He was driven out 1420, at this time the Turks’ support ensured that Tvrtko II was fully installed as Bosnian king ones more. Bosnia enjoyed a few years of peace in the early 1420s; but then the pattern of allegiances shifted again, with Tvrtko II turning to Hungary for help against the Turks, and also engaging in a territorial war against Serbian forces over the rich mining district of Srebrenica in eastern Bosnia. By the early 1430s his main rivals inside Bosnia, the nobleman Sandalj and King Ostoja’s son, Radivoj, were receiving help and encouragement from both Serb nobleman and the Turks, and had gained control over large part of Bosnia.
Tvrtko II held on to power in Bosnia until his death in 1433: these final years of his reign were marked by further Turkish raids (including the seizure of Srebrenica in 1440), and continuing growth in power of Stephen Vukčić, the lord of Hum. At first Vukčić refused to recognize Tvrtko’s successor, Stephen Tomaš, and several years of civil war ensued. In 1446 they came to an agreement, but Vukčić continued to give support to Serb ruler, George Branković, who, as a semi-independent vassal of the Turks, was still warring against the Bosnian king for the control over the Srebrenica region of eastern Bosnia. To emphasize his own independent status, Vukčić gave himself a new title in 1448: ‘Herceg of Hum and the Coast’. He later changed this to ‘Herceg of St Sava’ after the saint buried at Miloševo, in his territory. The word ‘Herceg’ was a version of the German Herzog (Duke), and the name ’Herzegovina’ derives from this title . Stephen Vukčić enjoyed few more years of power and prosperity, but in the early 1450s hi was embroiled not only in a war against Ragusa but also in a civil war with his own eldest son. The family dispute flared up again in 1462, when the son sought help from the Turks and encouraged them to include Hercegovina, along with Bosnia, in their plans for a massive assault in 1463.
The final years of Christian Bosnia were inevitably overshadowed by the Turkish threat. King Stephen Tomaš, desperate to secure promise of the outside help, turned in the 1450s to the papacy. Rome had taken an increasing interest in Bosnia in recent years because the papal authorities had become obsessed with the question of Bosnian heresy, and poured out a stream of documents in the 1440s accusing the Bosnian Church of a whole range of pernicious doctrinal errors, including Manichaeism. Renewed efforts were made by the Franciscans in the 1450s: one report by a papal legate in Bosnia in 1451 stated that ‘in places inhabited by the heretics, as soon as the friars arrive, the heretics melt away like wax before a fire’ . Then in 1459, King Stephen Tomaš agreed to change to a policy of direct persecution. He summoned the clergy of the schismatical Bosnian Church and offered them to choose: conversion to Catholicism, or expulsion from Bosnia. According to the later papal source, two thousand chose conversion, and only forty fled, taking refuge in Hercegovina . The back of the Bosnian Church was thus broken by the Bosnian king himself, just four years before the destruction of the Bosnian kingdom.
When Stephen Tomaš died in 1461 and was succeeded by his son, Stephen Tomašević, the end of Bosnia was clearly in sight. Tomašević wrote to pope in 1461, predicting a large-scale Turkish invasion and begging for help; he wrote again in early 1463 to Venice, warning that the Turks were planning to occupy the whole of Bosnia and Herzegovina that summer, and that they would then move on to threaten the Venetian lands in Dalmatia . But no help came. A large Turkish army under Mehmed II assembled in the spring of 1463 at Adrianople (Edirne), and marched on Bosnia.
The first Bosnian fortress to fall (on 20 May) was old royal stronghold of Bobovac; King Stephen Tomašević then fled north-westwards to Jajce, and took refuge in near fortress of Ključ. Besieged by the Turks there, he surrendered himself on a promise of safety. Various elaborate stories of his betrayal and his subsequent execution later grew up. But as it happens we have an eye-witness account in the memoirs of Serb-born Turkish janissary, whose description is chillingly matter-of-fact: ‘When the King’s servants, who were in the fortress, saw that their lord had been taken, they gave themselves up The Sultan took possession of the fortress, and ordered that the King and his companions should be beheaded. And he took his entire country into his possession.’ 
Bosnian royal symbol, the fleur-de-lys (Lilium bosniacum)
Despite its intermittent civil wars and invasions, Bosnia had achieved real prosperity during the high middle ages. The key to its wealth was mining: copper and silver at Kreševo and Fojnica; lead at Olovo; gold, silver and lead at Zvornik; and, above all, silver at Srebrenica. A roman gold-mine at Krupa (north-east of Gornji Vakuf) may also have functioned through the middle ages. The royal courts of Bosnia also had well-organized chancelleries, frequently manned, after the 1340s, by Franciscans; documents were written mainly in Bosnian variety of written language or script called Bosančica. Artists and craftsmen from Ragusa and Venice also came to work in Bosnia; little of their handiwork, alas, remain, but carving of good quality can be seen in the fragments of sculpture which have survived from King Tvrtko’s court at Bobovac, together with the capital of a column decorated with the Bosnian royal symbol, the fleur-de-lys . Of course Bosnia was not an important centre of European culture in the middle ages. But its provincialism should not be exaggerated. The noble families were well connected with a wider world of central European nobility; at the medieval Bosnian courts there were princesses from Hungary, Prussia, Bulgaria, Poland, Serbia, Italy and Greece .
1. Orbini mentions one abortive attempt during the reign of Stephen Kotromanić: Regno de gli Slavi, p. 354-355.
2. Miller, Essay on the Latin Orient, p.468; Coquelle, Histoire du Montenegro, p. 82.
3. Fine, Late Medieval Balkans, p. 146.
4. Miller, Essay in the Latin Orient, p. 473; Fine, Late Medieval Balkans, p. 148.
5. Fine, Late Medieval Balkans, p. 275-279.
6. Ibid., p. 384-386; Klaić, Geschichte Bosniens, p. 201-203; Ćirković, Istorija bosanske drzave, p. 135-140.
7. Thalloczy, Studien zur Geschichte Bosniens, p. 146-159; Fine, Later Medieaval Balkans, p. 577-578.
8. Fermendžin, Acta Bosnae, p. 211.
9. Fine, Bosnian Church, p. 332-333.
10. Fine, Late Medieval Balkans, p. 583-584 (to the Pope); Fermendžin, ed., Acta Bosnae, p. 252 (to Venice).
11. Lachmann, ed., Memoiren eines Janitscharen, p. 139-140.
12. Benac and Čović, Kulturna istorija Bosne, p. 422-431.
13. Ćirković, Historija Bosne, p. 9.
14. Noel Malcolm, Bosnia a short history; Pan Books 2002, p. 13-26.