I want to know the answer to the following question:
When were the Russian Empire, Serbia, and Montenegro the only free Slavic states in the world?
All the background I'm provided with is that "In 1918, after World War I ended, the Slavs established such independent states as Czechoslovakia, the Second Polish Republic, and the State of Slovenes, Croats and Serbs.". Is that enough to answer the question?
Answer: no