Why do we say "the 18th Dynasty" or "the 4th Dynasty"? The numbers come from one man, an Egyptian priest named Manetho, who lived in the early 3rd century BC under the first Ptolemies. He wrote a history of Egypt in Greek, the Aegyptiaca, using temple records and king lists like the ones in the last lesson.
Key idea
Manetho grouped the kings into 30 dynasties (a 31st was added later), from Menes to the last native kings. Historians still use his numbers. His book is lost; it survives only in quotations and summaries by later writers, such as Josephus, Africanus and Eusebius, which do not always agree.
Why it works
A dynasty for Manetho was a group of kings he could treat together, often named for the city they came from ("the 12th Dynasty, of Thebes"; "the 26th, of Sais"). Usually that meant one family, but not always. Sometimes the line changed with the capital, and in divided times two or three of his dynasties ruled at the same time in different places.
How his work reached us
- Manetho wrote in Greek for the new Greek-speaking rulers of Egypt.
- The Jewish historian Josephus (1st century AD) quoted parts of it, including the story of the Hyksos.
- Christian chronologists, Julius Africanus and Eusebius, made lists of Manetho's dynasties and reign lengths; later writers copied those.
- Copies of copies drifted: the same king can have different reign lengths in different versions.
Worked example: Overlapping dynasties
A list gives the 22nd Dynasty c. 945–715 BC and the 23rd c. 818–715 BC. Did the 23rd Dynasty follow the 22nd?
- If the 23rd followed the 22nd, it would begin after c. 715 BC.
- Instead it begins c. 818 BC, while the 22nd was still ruling.
- So the two dynasties ruled at the same time, in different parts of Egypt.
Answer: No: they overlapped.
Common mistake
Thinking a dynasty is always one family. Manetho's divisions sometimes follow a change of capital rather than of bloodline, and dynasties in intermediate periods often overlap. Adding up all his dynasties end to end makes Egyptian history far too long, a mistake some early scholars made.
Manetho's numbering is a convenience. It is so useful that every Egyptologist uses it, even while knowing its flaws.