Britannica Sources used in this answer

How were ancient Egyptian years and royal reigns recorded?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Side view of the Sphinx with the Great Pyramid of Khufu rising behind it on the Giza Plateau near Cairo, Egypt. — ancient Egypt Side view of the Sphinx with the Great Pyramid of Khufu (Cheops) rising in the background, Giza, Egypt.

In ancient Egypt, the recording of time and royal reigns evolved significantly over the civilization's history.

Recording Royal Reigns

The primary unit of time larger than a year was the reign of a king. Initially, years were not numbered consecutively; instead, each year was named after a major event, and these names were recorded in official registers alongside the height of the Nile’s annual inundation. By the 4th and 5th dynasties, this system shifted to assigning dates based on biennial cattle censuses.123

Eventually, the standard practice for dating documents became the regnal year system, expressed as "year 1, 2, 3... of King So-and-So," with the count resetting to year 1 upon the accession of a new monarch. To maintain historical records, the Egyptians compiled king lists—such as the Turin Papyrus—which documented consecutive rulers and the total length of their reigns.132

Chronological Frameworks

Because the Egyptians did not use eras longer than a single reign, historians reconstruct their chronology by aggregating these reign lengths and cross-referencing them with astronomical data, such as the heliacal rising of Sirius (Sothis). Fragments of early annals, most notably the Palermo Stone, provide essential, albeit incomplete, evidence for these early chronological records.1234