Chronology is the foundation of every archaeological research. Every single object, a text, or even the greatest monuments must be understood within their period of time. In certain occasions ancient authors have given a clear statement of the date of a piece but, even in these cases, we find ourselves with the task of translating ancient dates to our modern calendar system. To do that the first
... [Show full abstract] option that learned individuals should know is the history of the calendar itself. The aim of this study is to review the chronological development of time reckoning and calculation systems or calendars in Ancient Egypt from the rather unknown predynastic time to the late antiquity. Scholars have been researching this same topic for many years and in fact there is a rich amount of Egyptian records from ostraka, papyri, as well as monumental inscriptions from all periods of Egyptian history that mention the application and use of calendars in Egypt. However, the opinion of the specialists is still very far from consensus and so there are different theories about how the Egyptian calendar worked and how exactly it was calculated. The three mayor theories are those regarding a Nile based calendar, a moon based calendar and a calendar based in the heliacal rising of Sirius, the so called “Egyptian civil calendar”. All these theories have been proposed and documented by research and in fact all can be proven by archaeological and historical evidence. A long lasting discussion regarding when each one of these calendars was in fact in use in Ancient Egypt can be enlightened by a new point of view that contemplates the development of all three systems throughout all Egyptian history succeeding one another as a “chain reaction” and making every system a step in a long evolution along the centuries.