In the years following the decrees of the Treaty of Berlin a social drive for national unity grew, that manifested with varying intensity and through a range of actions, but was strongest in the Principality of Bulgaria and Eastern Rumelia. The relations between the two territories in the sphere of institution and army building, economy, and culture evolved upon the foundation of the unification. The powerful social movements reached their climax in 1885, when in September, the Bulgarian society, united by its cause and against the will of the Great Powers, declared the unification of the two Bulgarias. The recognition of this historic act proved to be a difficult process; the political elite went through great toils to alleviate the positions of the Great Powers who sought to restore the status-quo. The changed balance of power on the Balkan Peninsula, result of the Unification of the Principality and the Province, put Bulgaria in a difficult situation and forced Her to defend its cause not only in the field of diplomacy, but also at the theatre of war. The successful first step on the path to national unification and victorious outcome of the ensuing Serbian-Bulgarian War (1885) introduced the next item on the agenda: the country’s full political independence and the liberation of Macedonia and Adrianople Thrace.
These important events are presented through a wealth of artifacts—uniforms and equipment of soldiers of the Bulgarian army and of the Eastern Rumelia militia, flags, documents, and personal items of participants in the Unification, the Serbo-Bulgarian War, and the Ilinden-Preobrazhenie Uprising (1903).