Where Europe was divided (5)
I believe the answer is:
'where europe was divided' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for yalta that I've seen before include "Ukrainian resort" , "WW2 1945 conference town" , "City on the Black Sea, where Roosevelt, Stalin and Churchill met in 1945" , "Crimean port, scene of nineteen forty five conference" , "Crimean town famous for WW2 conference" .)