The Aegyptiaca (Ancient Greek Ἀιγυπτιακά, Aiguptiaka), the "History of Egypt", was Manetho's largest work, and certainly the most important. It was organised chronologically and divided into three volumes, and his division of rulers into dynasties was an innovation. However, he did not use the term in the modern sense, by bloodlines, but rather, introduced new dynasties whenever he detected some sort of discontinuity whether geographical (Dynasty IV from Memphis, Dynasty V from Elephantine), or genealogical (especially in Dynasty I, he refers to each successive Pharaoh as the "son" of the previous to define what he means by "continuity"). Within the superstructure of a genealogical table, he fills in the gaps with substantial narratives of the Pharaonic kings.
Some have suggested that Aegyptiaca was written as a competing account to Herodotus' Histories, to provide a national history for Egypt that did not exist before. From this perspective, Against Herodotus may have been an abridged version or just a part of Aegyptiaca that circulated independently. Unfortunately, neither survives in its original form today.
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