East Herzegovina

East Herzegovina (, Источна Херцеговина) is the eastern part of the historical Herzegovina region in Bosnia and Herzegovina, east of the Neretva river, part of the Republika Srpska entity. Major towns are Trebinje, Nevesinje and Bileća, predominantly inhabited by ethnic Serbs (see Serbs of Bosnia and Herzegovina). West Herzegovina is the western part, west of the Neretva river, and is today administratively part of the Herzegovina-Neretva Canton and West Herzegovina Canton, predominantly inhabited by ethnic Croats, located in the Federation of B&H entity. The easternmost parts of historical Herzegovina (the Duchy of St. Sava and Sanjak of Herzegovina) lie in Montenegro, in so-called "Old Herzegovina", which became part of the Principality of Montenegro in 1878. In 1991, local ethnic Serbs of the region declared the territory of SAO East Herzegovina independent and joined other Serb territories into Republika Srpska by 1992. The meso-region has since been named Trebinje Region (Regija Trebinje/).
Ottoman period.
In the first Otoman defters groups of Christian shepherds appear, declaring themselves as Vlachs who have settled in the empty parts of eastern Herzegovina. In that area, 1624 there were still 14 Catholic parish churches.
Culture.
The "Association of Municipalities of Herzegovina"