Peace Theories and the Balkan War - Norman Angell - Google Books

https://books.google.de/books?id=0iCz239mYPUC&pg=PA163#v=onepage

From 1258 onwards Bulgaria may be said to have continued flickering until its final extinction as a state in 1393, but during this period it never had any voice in controlling the destinies of the Balkan peninsula. Owing to the fact that no ruler emerged…