War broke out between Serbia and Bulgaria on 14 November 1885 as the result of a border dispute.

National Red Cross societies existed in both countries. On 20 and 24 November 1885 the ICRC asked neutral countries to provide assistance. Throughout the conflict, it was the Red Cross which was the main provider of care for the wounded, introducing hitherto unknown techniques of war surgery based on antisepsis.

At the request of the International Committee, the Austrian Red Cross established an international agency in Vienna on 4 December 1885 to deal mainly with the delivery of aid. It sent a delegate to Serbia and Bulgaria to visit hospitals, assess needs and organize the channelling of relief.

Lists of wounded and prisoners were exchanged through the Vienna Agency or directly between the Serbian and Bulgarian Red Cross societies.