The history of Ottoman Bulgaria spans nearly 500 years, from the conquest by the Ottoman Empire of the smaller kingdoms emerging from the disintegrating Second Bulgarian Empire in the late 14th century, to the Liberation of Bulgaria in 1878. As a result of the Russo-Turkish War (1877–1878), the Principality of Bulgaria, a self-governing Ottoman vassal state that was functionally independent, was created. In 1885 the autonomous province of Eastern Rumelia came under the control of the Bulgarian Tsar. Bulgaria declared independence in 1908.
The Ottomans reorganised the Bulgarian territories, dividing them into several vilayets, each ruled by a Sanjakbey or Subasi accountable to the Beylerbey. Significant parts of the conquered land were parcelled out to the Sultan's followers, who held it as benefices or (small timars, medium ziyamet and large hases) directly from him, or from the Beylerbeys. This category of land could not be sold or inherited, but reverted to the Sultan when the fiefholder died. The lands were organised as private possessions of the Sultan or Ottoman nobility, called "mülk", and also as an economic base for religious foundations, called vakιf, as well as other people. Bulgarians regularly paid multiple types of taxes, including a tithe ("yushur"), a capitation tax (jizyah), a land tax ("ispench"), a levy on commerce, and also various irregularly collected taxes, products and corvees ("avariz").
The Ottomans did not normally require the Christians to become Muslims. Nevertheless, there were many cases of individual or mass conversion, especially in the Rhodopes. According to Thomas Walker Arnold Islam was not spread by force in the areas under the control of the Ottoman Sultan. A 17th-century author said: