Razryad

A razryad () was a military administrative subdivision of the Tsardom of Russia from the 16th to the 17th centuries. Service class people living within razryads were obliged to enter military service and join razryad regiments. Each regiment incorporated several military units, including Streltsy, Reiters, dragoons, and other types of soldiers. Razryads were governed by the main organ for the administration of the Razryad Prikaz.
History.
Initially, territory in the Tsardom of Russia was subdivided into uyezds. As the territory of the Tsardom expanded, this administrative system encountered certain issues. The large number of relatively small uyezds that were directly governed by Moscow especially burdened the borderlands of the state, where officials called for the expansion of voivode authority to more efficiently organize troops. The first razryads, larger in size and geared toward military organization, were developed in these borderland uyezds.
The first razryad, founded in the 16th century, was centered in Tula. The Tula voivode directed urban and regiment voivodes from the Oka river to the Upa river. With the razryad, the Tula voivoide combined military and administrative authority, managed the collection of funds, and directed local authority. 
By 1616, the population of fortified towns designated as razryads reached 24,350. 
Each razryad was composed of several uyezds. As a result of the 1680 military and territorial reforms, the entire territory of the Tsardom of Russia became subdivided into 
9 razryads, and all service class people assigned among them. Service class people where divided among razryad regiments, and a permanent Bolshoi regiment was created for one of the borderland razryads. Razryads were primarily a military administrative unit, similar to contemporary military districts in the Russian Federation, and headed by razryad voivodes. Razryad voivodes were divided into both military and administrative positions of authority, in accordance with the defensive interests of each razryad. The razryads became an intermediate between central authority and the local uyezds, and paved the way for the creation of guberniya in the 18th century.