Abdul Hadi Pasha
Banned
First, let's get clear on definitions. I think the intial poster is really referring to "Islamification", not "Turkification", since the Ottomans had no particular identity as "Turks".
Regarding the question of blame for crimes against humanity, I don't think there's really a comparison between the 15th c, when warfare was a more or less permanent state everywhere, and the late 19th c, when we had supposedly evolved civilized rules of conduct.
Even taking that into consideration, the Ottomans were invited into Europe by the Byzantines, and while they certianly expanded, a very large proportion of Balkan conquests were defensive annexations in response to Christian "Crusades" - and in any case, the Ottomans had no intention of exterminating subject peoples and their cultures. In the 19th c, the goal of the Balkan powers and their Great Power sponsors was to utterly exterminate the Muslims of the Balkans, which is entirely more serious a matter from a moral perspective, both due to intent, and the context of the time.
I'm not sure I agree that this has an impact on Turkey's attitude toward human rights, but it does make them incredibly hostile to any whiff of separatism - as, in Ottoman/Turkish history, separatism has always been accompanied by the total destruction of the Muslim/Turkish population in territories lost. I think there is recognition that Turkey needs to improve its human rights performance, and by all measures they have made and are making enormous progress in that regard - but this issue isn't related to the past, except insofar as Turks have the aforementioned paranoia - justified - about separatism. Human rights today are a universal value, and the past is no excuse for behavior today.
With regard to the main question, the reasons are manifold:
1. The population of the Balkans was largely Islamified. In 1876 it was around 43% Muslim, and in earlier times was probably even more so. Superior security in the 16th c led to an inflow of Christian South Slavs, and in the 17th & 18th c, Christian population growth was higher due to massacres of Muslims by invading Russian and Hapsburg armies and by the death toll of Muslims who had to serve in the military, and the lesser wealth available to Muslims for this same reason - Christians were able to devote their entire energy to economic pursuits. After the Berlin settlement in 1878, the remaining Ottoman Balkan territory has a Muslim majority, which actually grew as Christians were more likely to emmigrate to the New World than Muslims, and this trend accelerated dramatically after the Young Turk revolution, which instituted universal conscription. The Christians demanded equality, but didn't really want it. The Tanzimat era reforms beginning in 1839 actually institutionally advantaged Christians over Muslims in most regards, and in addition the Christians had Great Power sponsors to reinforce these advantages.
2. Anatolia was conquered five centures earlier, and its population more sparse and easily assimilated. Even so, by WWI the population was probably abou 20% Christian, roughly evenly split between Armenians and Greeks. But if the Balkans had remained Ottoman, the percentage Muslim would certainly have increased.
3. Anatolia was conquered outside the context of the Byzantine Empire - the Balkans were largely subjected to regular Ottoman administration within the Byzantine context, by which I mean with the Patriarchate as an Ottoman governmental "department". This limited conversion somewhat.
Taxation really had nothing to do with anything, except that in earlier periods, people were somewhat more likely to covert to Islam as the taxes were lower, but this only made sense before conscription. After conscription was adopted, it made way more financial sense to pay the military exemption tax and avoid service, so there was no impetus to convert. Remember that the amount of taxes that could be levied on Christians was limited by Islamic law too - and in the later period, taxes were equal for everyone, except that the military exemption tax was impossibly high for Muslims, whereas Christian businessmen could adopt foreign citizenship and avoid virtually all taxation.
Regarding the question of blame for crimes against humanity, I don't think there's really a comparison between the 15th c, when warfare was a more or less permanent state everywhere, and the late 19th c, when we had supposedly evolved civilized rules of conduct.
Even taking that into consideration, the Ottomans were invited into Europe by the Byzantines, and while they certianly expanded, a very large proportion of Balkan conquests were defensive annexations in response to Christian "Crusades" - and in any case, the Ottomans had no intention of exterminating subject peoples and their cultures. In the 19th c, the goal of the Balkan powers and their Great Power sponsors was to utterly exterminate the Muslims of the Balkans, which is entirely more serious a matter from a moral perspective, both due to intent, and the context of the time.
I'm not sure I agree that this has an impact on Turkey's attitude toward human rights, but it does make them incredibly hostile to any whiff of separatism - as, in Ottoman/Turkish history, separatism has always been accompanied by the total destruction of the Muslim/Turkish population in territories lost. I think there is recognition that Turkey needs to improve its human rights performance, and by all measures they have made and are making enormous progress in that regard - but this issue isn't related to the past, except insofar as Turks have the aforementioned paranoia - justified - about separatism. Human rights today are a universal value, and the past is no excuse for behavior today.
With regard to the main question, the reasons are manifold:
1. The population of the Balkans was largely Islamified. In 1876 it was around 43% Muslim, and in earlier times was probably even more so. Superior security in the 16th c led to an inflow of Christian South Slavs, and in the 17th & 18th c, Christian population growth was higher due to massacres of Muslims by invading Russian and Hapsburg armies and by the death toll of Muslims who had to serve in the military, and the lesser wealth available to Muslims for this same reason - Christians were able to devote their entire energy to economic pursuits. After the Berlin settlement in 1878, the remaining Ottoman Balkan territory has a Muslim majority, which actually grew as Christians were more likely to emmigrate to the New World than Muslims, and this trend accelerated dramatically after the Young Turk revolution, which instituted universal conscription. The Christians demanded equality, but didn't really want it. The Tanzimat era reforms beginning in 1839 actually institutionally advantaged Christians over Muslims in most regards, and in addition the Christians had Great Power sponsors to reinforce these advantages.
2. Anatolia was conquered five centures earlier, and its population more sparse and easily assimilated. Even so, by WWI the population was probably abou 20% Christian, roughly evenly split between Armenians and Greeks. But if the Balkans had remained Ottoman, the percentage Muslim would certainly have increased.
3. Anatolia was conquered outside the context of the Byzantine Empire - the Balkans were largely subjected to regular Ottoman administration within the Byzantine context, by which I mean with the Patriarchate as an Ottoman governmental "department". This limited conversion somewhat.
Taxation really had nothing to do with anything, except that in earlier periods, people were somewhat more likely to covert to Islam as the taxes were lower, but this only made sense before conscription. After conscription was adopted, it made way more financial sense to pay the military exemption tax and avoid service, so there was no impetus to convert. Remember that the amount of taxes that could be levied on Christians was limited by Islamic law too - and in the later period, taxes were equal for everyone, except that the military exemption tax was impossibly high for Muslims, whereas Christian businessmen could adopt foreign citizenship and avoid virtually all taxation.