When talking about Islam in South europe we automatically think of the Ottoman Turks who were responsible for spreading it throughout this region.
In order to understand the reaons why the local population accepted Islam or why certain Moslem groups moved to Europe, we have to look at the Ottoman state particularly its political and religious aims. These aims have been the result of Ottoman policies shaped and reshaped from the time of their first arrival in Europe in the second half of the 14th century when the frontier warriors of Orhan established themselves in the Gallipoli peninsula. The first period was marked by the establishment of vassal Christian states, whose leaders and inhabitants were assured of their possessions and free performances of their religion; a realistic attitude held by a conquering power aware of the difficulties of controlling and policing large subject territories. It was also the first sign of Ottoman political realism, which influenced their attitude toward the conquered Christian population, and formed a compromise with existing ideas of Moslem ideology and conquest.
According to basic Moslem ideology the world is divided into two halves: dar-al-islam (the world under Moslem control) and dar-al-harb (non-Moslem countries at war with islam and, according to the Koran, countries eventually to be conquered and converted to Islam. This ideology supported a state of permanent war, whch was certainly the case during the first period of the conquering and victorious Ottomans between 1350-1570. The gradual decline of Ottoman power as well as the creation of more permanent frontiers in the Balkans, influenced the Ottoman policy toward Islamisation and contributed towards the stabilisation and continuity of the Ottoman state structure.
Since the beginning of the Ottoman state in Asia Minor, Christians, albeit as a minority were a permanent feature and part of that political entity. These were mostly Orthodox, originally inhabitants of the diminishing Byzantine state. This also explains the particular position of the Orthodox church, the representative of all Christian groups, Orthodox or not, within the Ottoman state.
This long experience with Christian minorities finds its original expression in Arab tribal society at the time of Mohammad, when the tribal system served as the basic pattern for structuring Moslem attitudes toward Christians. The traditional system of patron-client relationships, existing between different tribal groups, became the basis of their relationship with Christians and Jews in Arabia. This system, better known as dhimma, offered the protection of a Moslem host tribe to a non-Moslem tribe, and guaranteed free performance of religion and preservation of traditional custom in return for a payment of dzyzya (poll-tax) and recognition of Moslem suzerainty. It was an asymmetrical relationship between two partners, one of whom acknowledged the supremacy of the other in return for religious and local autonomy within the limits of certain restrictions.
The dhimma system became the legal basis of religious tolerance in Moslem political and religious structure and was also adopted by the Ottomans. As a matter of fact, it is very probable that Ottomans coming from Central Asia to Asia Minor accepted Islam under similar conditions, namely, preservation of their customs in return for acceptance of Islam; which, being a religion of aggressive conquerors, must have been very attractive to warlike Turkish nomads who, by their conversion to Islam, received an ideological basis for their wars of conuest. After explaining the emergence of such basic moral and legal attitudes toward conquered Christians, we have to consider alterations in these attitudes in relation to the changing situation within the Ottoman empire. As long as the Ottomans were victorious conquerors, attitudes toward Cjrostoams were more generous, since the rulers knew that they did not have to fear people who were willing to submit to the Ottomans in return for some autonomy in local or religious affairs. In addition, the frontiers were far from Istanbul, and Christians did not represent a serious threat to Ottoman power. This period coincides with a period of consolidation and highly centralised and efficient Ottoman state organization. There was also a practical consideration: the empire, always in need of more money for its armies in the field, attached more importance ot large taxes, coming largely from Christian subjects, than to exposing those subjects to forcible conversion and thus diminishing the state coffers. In spite of that, Islamisation did take place, but always within clearly defined limits.
One particular group which relatively quickly accepted Islam was that of the professional soldiers. In the early stages of Ottoman rule various Christian professional military groups served in the Ottoman army (eg. vojnuks or sipahis up to the 16th century or martoloz up to the 18th.). Sipahis were, of course, a feudal type of cavalry, who served in many military campaigns in return for fiefs which they received from the Sultan. In the 14th and 15th centuries many of them were Christians. One of the practical reasons for conversion of professional soldiers must have been the attraction of becoming, as Moslems, eligible for the highest posts in the empire. The latter must have proved a considerable attraction to the soldiers, especially since, in the 15th and 16th centuries, the Ottoman armies were winning on most battlefields.
Another occupational group which quickly adopted Islam was that of the miners in Bosnia and Serbia, often Catholic Saxons who in return for conversion received considerable privileges.
The third group of converts was represented by members of the local nobility, who tried in this way to keep their property and positions in their former territories. Already before the conquest the Ottomans had directly intervened in different disputes between the Balkan nobility and their proteges who often became converted to Islam after the conquest. This also explains why some areas submitted quickly to the invading Ottoman armies. Conversion was the price of preserving their privileges or even increasing them in the Ottoman political structure. Such converts included even members of the Paleologue imperial family who enjoyed large properties in Bulgaria (15th and 16th centuries). Some of the prominent converts built up eminent careers like Ahmed Pasha Herzeg Oglu, the youngest son of Herzeg Stjepan, ruler of Hercegovina, who married a daughter of Sultan Bayazid II and became four times Grand Vezir and later army commander against Egypt under Selim I. Another interesting case was that of Ahmed Pasha Dukadjin, originally from North Albania where his noble family was related to the Byzantine imperial family of Comnens. He commanded an army against Persia and was a Grand Vizir in the early 16th century. A number of similar examples could be given. All the above accounts are related to social and financial rewards, which explains the fact that Islamisation was used as a means to a particular end. Such rewards also obviously acted as mechanisms for the peaceful spreading of Islam.
Another mechanism of Islamisation was the creation of towns, which became not only centres of the Ottoman administration, but also of the Islamic way of life. After arriving in the Balkans, the Ottomans made the existing towns centres from which further conquests could have been organised. They created many towns like Sarajevo, Yeni Pazar (Novi Pazar), and, in addition a number of towns already in existence acquired a large Moslem majority, like Istanbul, Sofia, Skopje, Prizren, Skutari and many othes. Some of the towns became very rich, which attracted Moslems and Christians alike, contributing toward Islamisatin of the peasant population which flocked to the towns and settled there. Urbanizatin and the spreading of Islam became closely related, even if not synonymous, as parts of the town population always remained Christian or Jewish. Prestige related to urbanisation, and Islamisation in the Balkans can be compared to similar processes in West or North Africa or some parts of Asia.
A special case of peaceful conversion to Islam is Bosnia, where, shortly after the conquest in 1463 a considerable number of Christian inhabitants, peasants and lesser nobility adopted Islam. Many of them belonged to a Christian sect called the Bogomils, who, after being expelled from Serbia, Bulgaria and other Balkan countries settled down in Bosnia where they formed a kind of national church. The Bosnian kingdom was troubled by both Hungary and Rome, and, as a result of this the Bogomils' religion became an expression of Bosnian independence and national identity. It received support even from the court which was officially Catholic. After the Ottoman conquest many Bogomils accepted Islam at least formally since it did not make too high demands on them. On the other hand it secured them a future in the new political situation.
Besides the peaceful spreading of Islam, forcible measures were also adopted, which were used eventually to increase the Moslem population of South Eastern Europe. In this respect the notorious system of devshirme or "tribute in blood" immediately springs to mind. Devshirme is the Ottoman term for the periodic levy of Christian children for training to fil the ranks of Janissaries, and to occupy posts in the service of the court and the administration. Literally the term means "collecting of Dhimma children" or the collecting of children of those under Moslem protection. It is uncertain when it started, but the first contemporary reference is from saloniki in 1395. Most of the Christian population of Rumeli (European Turkey) were subject to devshirme, but exemptions were made (eg. children of craftsmen and the urban population were excluded as were the islands of Rhodes and Chios because of voluntary submission and guardians of passes or miners because of their valuable service to the Ottoman state).
In political terms devshirme was a system by which the Sultan filled all important posts with his own men and kept the old Ottoman aristocracy away as they could have become dangeorus for his throne and dynasty. The devshirme system is certainly closely related to the idea of a highly centralised system with a Sultan as its centre of power. In sociological terms it was the channel through which even the humblest peasant could achieve the highest post in the empire providing he showed ability, while becoming completely subordinated to the Sultan, his supreme master and centre of all the power of the Ottoman state. It should not be forgotten that many of the Grand Vezirs came from the devshirme, not to mention thousands of army commanders, administrators and officials.
The second means of forced Islamisation was through the system of deportation of nomads, Shia groups from Asia Minor, or other rebellious elements, to the Balkans, and colonisation there. In some cases (anatolia in the 15th century) the population was shifted because of demographic pressure. Some of these nomads were Yuruks who were settled in Thrace, Macedonia and Dobruja, all conquered in the early period of the Ottoman penetration. Some Turkish immigrants accompanied the conquering armies and settled around Skopje and other centres of early Ottoman rule, forming the nucleus of Moslem population in the frontier marches from where the rest of the Balkans was eventually occupied. The topography of that part of the world indicates very often how such villages of deportees and colonisers came into existence. In order to make such deportations easier, deportees and colonists received special privilegs such as smaller taxes, advantages in getting land, etc. These people included nomads, idlers, and criminals and later, peasants and craftsmen. As a result of this policy the number of Moslems increased, and between 1520-30 a census shows 833,000 Christian housholders versus 194,000 Moslem ones ( a quarter of the total population was Moslem).
the situation changed after the Ottoman frontiers became more static and the state had to accept defensive rather than offensive measures in order to preserve the Ottoman state structure and political "status quo".
Fighting two Christian powers, Austria and Venice, the Ototman state cleverly maniupualted the Orthodox Church in the Balkans against two Catholic powers, and the disputes between the two churches were widely exploited by the Ottomans. In spite of that the position of the tolerated Christian majorities did change in the 17th and 18th centuries. They became more exposed to pressures and chicaneries by local administrators, who gained more and more control as the central power became less and less efficient and impartial. This process eventually contributed towards the chaos, hasty reforms, and eventual collapse occurring during the 18th and 19th centuries.
Finally, we should consider two serious attempts at forced mass conversion to Islam under Selim I and Murad III (16th century). Both of these attempts failed as the Ulemas persuaded the Sultans to change their minds, because of direct opposition to Shari'a (the dhimma contract) and the prospect of considerable financial loss if a hitherto Christian, and therefore heavily taxed, populace became Moslem.