Recently it has become standard in the Western world to refer to dates prior to the birth of Christ as B.C.E. (before the Common Era), replacing the earlier B.C. (before Christ) usage. This convention is an effort to become less Christian-centered and Eurocentric in our use of language, although the chronology remains linked to the birth of Jesus. Similarly, the time following the birth of Christ is referred to as C.E. (the Common Era) rather than A.D. (Anno Domini, Latin for “year of the Lord”). Dates in the more distant past are designated in this book as BP (before the present) or simply as so many “years ago.” Of course, these conventions are only some of the many ways that human societies have reckoned time. The Chinese frequently dated important events in terms of the reign of particular emperors, while Muslims created a new calendar beginning with Year 1, marking Muhammad’s forced relocation from Mecca to Medina in 622 C.E. As with so much else, the maps of time that we construct reflect the cultures in which we have been born and the historical experience of our societies.