Could the Peloponnesian Wars have occurred in the 12th century AD? This and other outlandish claims are given serious credence in this book and investigated in earnest. Seemingly, that is reason enough to put the book down (this comes up first on page 13) and move on to a more worthwhile read. But, that would do a disservice to the positive elements of this book. Basically, the Lost Millennium is a look at the science of chronology, or dating events and putting them in some kind of order. How do we date events? Sounds like a simple question, right? We just look at old sources and calculate the date. In fact, the techniques used to date events are quite complex. Sources cause numerous problems, such as dating based on dynasty. If we can't ascertain the date of the dynasty... and so on. So, a more concrete tool historians have used have been things like records of eclipses. Because astronomy is a fairly well developed science, we can determine when eclipses occurred and what kind of eclipses they were (lunar, solar, full or partial). Then, we merely need to find a reference in the texts which correlates to that kind of eclipse. For example, the Peloponnesian Wars coincided with a series of eclipses. Thus, the Peloponnesian Wars have been used as somewhat of a standard by which to date other events. Some scientists have questioned the dates which the scholarly consensus has arrived at, including heavy weights like Isaac Newton and modern revisionists like Velikovsky and Morozov (one of the main theorists discussed in this book). The heart of this book is basically a scientists attempt at chronology, without using "unreliable" historical records such as political histories but instead, utilizing "reliable" records such as eclipses and other astronomical phenomena to the exclusion of any other historical sources. This approach leads to some ridiculous conclusions (above). In the end, the author himself basically debunks Morozov's theories (although rather gently I felt). The impression I was left with was that scientists who want to ignore the entire corpus of historical knowledge are just as out of place in history as a historian would be who wanted to ignore the corpus of scientific knowledge. One thing which I immediately realized was that all the European records could easily be checked by referring to Islamic sources which mention events in Europe. Because the muslims dated things based on the Hijra, which we can ascertain and kept careful records after that point, due to the ritual importance of the lunar and solar cycle for things like Ramadan and prayer times, their records are rock solid. Another feature of this book which history buffs will enjoy is its summary of various techniques for dating events. In addition to the astronomical information, there are brief summaries of carbon dating, dendrochronology (tree ring dating, which is apparently not as great as I thought, for example, trees gaining 5 rings in one year in some cases!) and thermoluminescence. I found these to be very concise and helpful, not only explaining the actual methods, but also the critiques leveled against them. A good read and I feel guilty that I got it on sale for a pittance of $2.