 The Great Idea ( <unk> <unk> ) , the dream of uniting all Greek populations of the Ottoman Empire , thereby restoring the Byzantine Empire under Christian rule , led him to contemplate entering the Crimean War on the side of Russia against Turkey and its British and French allies in 1853 ; the enterprise was unsuccessful , and resulted in renewed intervention by the two Great Powers and a second blockade of Piraeus port , forcing Greece to neutrality . 
