Before the 19th century, western Montenegro was nothing more than a cluster of feuding tribes presided over by the Metropolitans of Cetinje. Montenegrin territory consisted of four small districts (), the most important of which was the Katuni "nahiya" with its nine tribes (Cetinje, Njeguši, Ćeklići, Bjelice, Cuce, Čevo, Pješivci, Zagarač, and Komani). These areas had been "de facto" independent from the Ottoman Empire since the Treaty of Passarowitz in 1718, though elements of self-governance had existed since the earliest days of Turkish rule in the 15th century. For decades, Ottoman authorities treated the inhabitants of western Montenegro and eastern Herzegovina as unsubjected "filuricis" who were only obligated to pay a fixed amount of Florentine ducats ("florin") to the Ottomans each year. Such taxation did not increase with the wealth or size of one's household, and Serbs in these regions were completely exempt from the Ottoman poll tax and other levies usually paid by Christian subjects to the Sublime Porte. Though the privileges granted the highlanders were meant to allay public dissatisfaction in these poor but strategically vital regions on the Venetian border, by the late 16th century, they ended up having the opposite effect. The Serbs began shunning Ottoman tax collectors entirely, and when the Ottomans attempted to impose some of the taxes normally paid by other Christian subjects, the Serbs revolted and carved out their own autonomous region. Absence of Ottoman authority produced an ideal opportunity for tribalism to flourish. Thousands of Serbs who remained in Ottoman-held territory converted to Islam to avoid paying these newly imposed taxes. Converts were granted full rights and privileges as Muslim subjects of the Sultan, while non-Muslims were viewed as second-class subjects and treated as such. Hence, Christians viewed all converts with derision and considered them "traitors to the faith of their forefathers". Religious killings were common in times of war since both Christians and Muslims considered members of the opposing faith to be apostates worthy of death.