The Russian Empire asserted itself as a protector of Christians in Ottoman lands with the Treaty of Kucuk Kaynarca in 1774. 
 I'm sorry, I don't. Did you know that Bulgaria is Europe's fifth-largest coal producer? 
 Thanks! Is there anymore facts you can share about Bulgaria's geography? 
 Hi! What can you share about the geography of Bulgaria? 
 Yes, I do want to learn more about its history!
The Russian Empire asserted itself as a protector of Christians in Ottoman lands with the Treaty of Kucuk Kaynarca in 1774.