Byzantine–Bulgarian wars
Byzantine conquest of Bulgaria
Byzantine–Bulgarian war of 913–927
Byzantine–Bulgarian treaty of 815
Byzantine–Bulgarian war of 894–896
Byzantine–Bulgarian treaty of 716
Sviatoslav's invasion of Bulgaria
Bulgarian Greek Catholic Church
Bulgaria (theme)
Uprising of Asen and Peter
Battle of Skafida
Uprising of Petar Delyan
Bulgarian Greek Catholic Eparchy of Sofia
Empire of Nicaea
Theodore II Laskaris
Constantine VI
Russian Orthodox cross