Srbska Krajina

When Croatia declared independence (in 1991) native Serbs living there proclaimed Serbian autonomous region Krajina (so called Kninska Krajina). On a referendum held on May 12th, 1991, more than 90% of electors voted for annexation with Serbia. Also, native Serbs, helped by Yugoslav army, started attacking Croatian cities to conquer as much territory as possible. Initially, the Serbs controlled about one-third of the country, declaring their territory the republic of Srbska Krajina (on February 26th, 1992). In 1993 they started issuing own stamps:

In 1995 Croatian army defeated Krajina and liberated much of its territory during operations 'Thunder' and 'Storm'. After those military operations Serbs controlled only a small territory in Eastern Slavonia (NE part of Croatia). This entity was renamed into Sremsko Baranjska Oblast which continued issuing stamps:

In 1998 this 'state' peacefully reintegrated into Croatia and ceased issuing stamps.