Fifty years ago when the World Atlas of Wine , Hugh Johnson's other book - Wine, The Signet book of Wine, and Time Life's Wines and Spirits were all published, the world of wine was smaller. California wines were in their infancy and grape wine variety options were smaller. In other words it was easier to be 'knowledgeable" There were no mentionable wineries in the US outside of Northern
California, there were too few to mention in South America , Asia, Africa, Australia, or Canada. Today the subject has really expanded to the point that it is difficult to write a comprehensive book about wine, at least not in a single volume. One would need several volumes just to have the wine labels pictured.