Amyrtaeus: only pharaoh of the twenty-eighth dynasty, revolted against the Persians in 404. He was still establishing his power when he died in 398.
To understand Amyrtaeus' coup, we need to know a bit more about the situation first. In April 404, the Persian king Darius II Nothus died, and his crown prince Artaxerxes II Mnemon succeeded to the throne. It was not uncommon in the Achaemenid empire that at the moment of succession, subject nations revolted. Amyrtaeus of Sais was the leader of an Egyptian insurrection that started in 404. Under normal circumstances, the new king would have sent a reliable general to repress the rebellion. This time, however, things were complicated because the new king had an ambitious and energetic younger brother, Cyrus. Almost immediately, a quarrel broke out, which escalated to civil war in the summer in 401. Cyrus was finally defeated at Cunaxa near Babylon.
During the battle, there were Egyptian soldiers in Artaxerxes' army. We do not know whether these men accompanied a regiment of Persian soldiers that had been transferred to defend Babylonia against the invader. The alternative is that they were the only troops from Egypt. The answer to this question is important to evaluate the policy of Artaxerxes. If they accompanied a part of the Persian garrison in Egypt, the country along the Nile was undergarrisoned, which may explain why Amyrtaeus could be successful. On the other hand, if the native Egyptians were the only troops transferred to Babylonia, it suggests that Artaxerxes was aware of the unquiet situation in Egypt, and used these soldiers not only to defend the heartland of his empire, but also as hostages. Unfortunately, we cannot give an answer to this question, which is in fact the question to what extent Artaxerxes was responsible for the loss of Egypt.
However this may be, the Egyptian rebel was a man who could inspire loyalty. His grandfather, also called Amyrtaeus, had been the leader of an earlier rebellion (463-461), but his father Pausiris had come to terms with the Persians and had served king Artaxerxes I Makrocheir with distinction. The Amyrtaeus who revolted in 404 knew how the Persian government worked and upheld a family tradition.
Amyrtaeus seems to have concluded an alliance with the Greek town Sparta: the Greeks would invade Asia, and Egypt would send them grain. In this way, the Persian army would be employed in Asia and Egypt would be left alone.
The rebel king was successful. For two generations, the Persians were unable to reconquer Egypt. But it is not clear how great Amyrtaeus' power actually was. A loan contract found in Elephantine in the south, possibly dated to the fifth year of his reign, suggests that he was master of Upper Egypt in 400, but the overall impression is that Amyrtaeus' kingdom remained unstable.
The instability of Amyrtaeus' rule is also suggested by the fact that at the end of his reign, he was removed from the throne by a man named Nepherites I, the founder of a new dynasty, the Mendesian or Twenty-ninth.
Amyrtaeus left no monuments. It is possible that he used the throne name Psamtik.