In the Ottoman Empire, a kaza was originally a "geographical area subject to the legal and administrative jurisdiction of a kad?. With the first Tanzimat reforms of 1839, the administrative duties of the kad? were transferred to a governor (kaymakam), with the kad?s acting as judges of Islamic law. In the Tanzimat era, the kaza became an administrative district with the 1864 Provincial Reform Law, which was implemented over the following decade. A kaza unified the jurisdiction of a governor (kaymakam) appointed by the Ministry of the Interior, a treasurer (chief finance officer), and a judge (kad?) in a single administrative unit. It was part of efforts of the Porte to establish uniform, rational administration across the empire.
The kaza was a subdivision of a sanjak and corresponded roughly to a city with its surrounding villages. Kazas, in turn, were divided into nahiyes (governed by müdürs and mütesellims) and villages (karye, governed by muhtars). The 1871 revisions to the administrative law established the nahiye (still governing a müdür), as an intermediate level between the kaza and the village.