What are the 50 events in American history that “changed America forever”? Finding consensus among historians on this issue would be nearly impossible; selecting the top ten might be easy (Columbus’s voyage, the Civil War, Reconstruction, the New Deal, the Civil Rights movement, etc.) but selecting nos. 11 through 20,21 through 30, and so on would spark endless debate.

The editors of What Happened? An Encyclopedia of Events That Changed America Forever have done a good job of selecting, describing, and interpreting the 50 events in American history that in their view had the most lasting impact on the nation. This is not a purely alphabetical encyclopedia like the venerable Dictionary of American History (Scribner’s, 2003), nor a series of alphabetical encyclopedias for ten periods of U.S. history, as is the Encyclopedia of American History (Facts on File, 2003). It lists the 50 events in 4 volumes in rough chronological order. The entries average about 25 pages and include an introduction presenting the historical facts, an interpretive essay written by a specialist in the field, entries on 5 or 6 important people and events pertinent to that event, and the text of one or two significant documents. Appendixes in each volume include a timeline and a glossary.

Reference librarians may assume by the title of this work that it is a guide to battles, discoveries, riots, or the passage of landmark treaties or legislation. However, the editors have interpreted “events” to be broad social, political, and religious phenomena that in some cases span decades. The Lewis and Clark expedition does not get its own entry, but rather is one of the sub-entries under “Louisiana Purchase”; similarly, the Cuban Missile Crisis is a sub-entry under “Cold War, 1946–1991.”

While the entries on the New Deal, Civil Rights movement, etc. are of high quality, this is material that will be well covered in most reference collections. What makes this work interesting and potentially valuable are the entries such as the “Suburbanization and Consumerism, 1945–1990” and “The Rise of Television, 1948–2010.” Although not covered in many traditional historical reference works, these “events” have had an incalculable impact on modern American life.

What Happened? An Encyclopedia of Events That Changed America Forever is fairly expensive and could gather dust if reference librarians don’t remember to incorporate it’s excellent entries into their recommendations for users who want to research a broad topic in American history. The essays provide a nice intermediate level of coverage for the researcher who doesn’t want to start with a book, yet more extensive that a general or historical encyclopedia.