What important event in 1917 that forced key Bolsheviks such as Lenin to go into hiding does this photo below portray?

The peace treaty signed between Russia and Germany that ended the First World War was signed where?

In which month of 1917 did Lenin finally return to Russia? Write your answer as a word, for example November. (November is not the right answer by the way!)

The period after the February Revolution was known as dual power.