In 1902 Russia and Austria-Hungary forced Serbia and Bulgaria to cut all ties with IMRO [Internal Macedonian Revolutionary Organization].
In 1903 Macedonian liberation forces staged a widespread revolt, the Ilinden-Preobrazhensko Uprising. Despite strong public support for the Macedonian cause, Bulgaria sent no help, and the Turks again suppressed opposition with great violence. Large numbers of refugees now entered Bulgaria from Macedonia...
After the death of its leader Gotse Delchev in the 1903 uprising, IMRO's influence decreased. Bulgarian public sympathy for the Macedonian cause also diminished, and by 1905 the government's attention turned to internal matters.
To strengthen its claim to Macedonia against its rivals Serbia and Greece, Bulgaria established (1899) a Macedonian Commission. Run from the Bulgarian capital of Sofia, the commission's object was to make Macedonia autonomous but controlled, with the permission of the Ottoman Empire (Turkey), by a Bulgarian inspector. Part of the Bulgarian plan to force a diplomatic maneuver through covert terrorist activity; and to this end, Bulgaian revolutionary bands called komitadji were sent on raids into Macedonia. They helped precipitate insurrection within the country in 1902-03. The komitadji murder of a Rumanian professor opposed to the arguments of the commission and their capture of a female American missinoary forced Austria and Russia to suggest reforms in the vilayets (administrative divisions) of Salonika, Monastir (Bitola), and Kossovo (1903). Accepted by the Ottomans, these reforms were never impremented. Further internal strife led inexorably to the First Balkan War and the division of Macedonia among the three rival claimants.