"the pressure to abolish slavery generally came from some combination of European colonial powers and economic and demographic shifts. A few Muslim clerics, such as one writing in the mid-nineteenth-century Arabian peninsula, opposed abolition on the grounds that slavery was accepted in religious texts. Similarly, one scholar argues “that slavery enjoyed a high degree of legitimacy in Ottoman society. That legitimacy derived from Islamic sanction,” among other factors. Although abolition did eventually occur, there was not a strong internally developed critique of slaveholding based on religious principles."