The book is dedicated to the dating of the Nativity of Christ, obtained by the authors, to 1152 AD. e. (with a January or September beginning of the year; in today's usual January years this would be December 25, 1152 AD or December 25, 1151 AD, respectively) and the resulting reconstruction of the history of the 12th century. This dating was first obtained by the authors in 2003 and has since found numerous confirmations. The book contains only new results. This is the second edition, corrected and expanded. The indicated dating of the era of Christ is final, since it was obtained using independent natural scientific methods. It is in perfect accordance with statistical parallelisms, which allows us to generally complete the reconstruction of the written history of mankind, starting from the era of the birth of writing in the 10th–11th centuries. A new step in the reconstruction of universal history allows us to take a completely different look at the place of Russian Orthodoxy in Christianity. The authors do not touch upon issues of faith and theology at all and, in particular, do not discuss any of the church dogmas. The book deals exclusively with issues of a historical and chronological nature. As the authors note, the reconstruction they propose is still speculative. At the same time, the authors are responsible for the accuracy and reliability of the dating they calculated. The book is intended for a wide range of readers interested in the history of Christianity, the history of Rus' and new discoveries in the field of new chronology.