The edition I read back in the mid-1960's was the first Mentor books paperback edition published in April 1962, and so reflects the state of the Soviet Union and the world as of that date. For me at the time, it was an excellent survey of Russian history from the earliest times, through the Middle Ages, the Tsarist period and the Soviet era up to the time of publication. Being introductory, it doesn't answer all the questions one might have, so that is a spur for further reading and there are a couple of pages of suggestions for further reading.