Islam began to spread first in the urban centres. The more complex nature of urban life spurred town-dwellers to adopt the rulers' religion. The influence of Islam was felt there first. On the one hand, the cities were the first centres of the conquerors' administration and target of colonisation. On the other hand, they were places of concentration of Christians and Jews owning large moneyed capital. Their basic ambition in the new social and political setting within the framework of the dominant Muslim state system was to further retain their leading positions. 

In the early period following the conquest of the Balkan towns, up to the middle of the 16th century, when the Ottomans believed it was their right and duty first of all to consolidate their power in the new territories and their participation in the later campaigns of conquest, the propertied urban groups managed to keep their predominance in the most important activities - tax farming, trading, crafts, etc. 

In the second half of the 16th century, parallel with the spread of Islam, the holders of money capital who professed Islam gained strong positions in the cities. The role of the Christians began to decline and they were forced to give up their place in the key economic activities to their Muslim fellow-citizens. In order to keep their positions, the most powerful Christian urban classes strove for proximity with the Muslim ruling crust by way of Islamisation. 

In the villages, unlike the towns, the spread of Islam began much later and followed its intrinsic rules, forms and motives. The delayed diffusion of Islam in the rural areas was mainly due to objective factors. The colonisation, especially in the Albanian highlands, did not affect so directly the rural population as it did the urban one. Wherever Ottoman settlers moved in, they aimed to establish separate colonies and live in relative isolation from the local population. The rural structures were characterised by isolation, which was quite pronounced in some places (especially in the highland areas), and which was hardly susceptible to outside influence. Very strong in the rural communities was the tradition of strict abiding by the customary law, of observance of the clan or mundane religious rites, of preserving their inherited, generation-old moral value system. The more or less homogeneous social structure of the rural population was also a factor making the cases of conversion to the dominant religion by personal and social motives, so characteristic of the urban areas, isolated and untypical in the countryside. 

The Ottoman authority did not aim to impose Islam among the rural populace forcibly and on a mass scale, since such an act would have harmed seriously the military and economic interests of the state. Bosnia made an exception, on political and military-strategic grounds, although the amount of the cizye, and some other taxes collected in this province, were valued high as revenues to the treasury, and no violent measures were applied. Ottoman centralism rarely resorted to campaigns for the spread of Islam. In Albania and Kosovo, where colonisation was scarce, and at places it was limited to the settlement of representatives of the Ottoman administration and the establishment of garrisons, Islamisation began latest in time. As evidenced by the reports of the Vatican Catholic inspectors, by the first decade of the 17th century only 10 per cent of the population in the Albanian North were Muslims.⁶⁹