The Twenty-eighth Dynasty of Egypt (notated Dynasty XXVIII, alternatively 28th Dynasty or Dynasty 28) is usually classified as the third dynasty of the Ancient EgyptianLate Period. The 28th Dynasty lasted from 404 BC to 398 BC and it includes only one Pharaoh, Amyrtaeus (Amenirdis), also known as Psamtik V or Psammetichus V. Amyrtaeus was probably the grandson of the Amyrtaeus of Sais, who is known to have carried on a rebellion in 465–463 BC with the Libyan chief, Inarus (himself a grandson of Psamtik III), against the satrapAchaemenes of Egypt.
As early as 411 BC, Amyrtaeus, a native Egyptian, revolted against Darius II, the Achaemenid Persian King and the last Pharaoh of the 27th Dynasty. Amyrtaeus succeeded in expelling the Persians from Memphis in 405 BC with assistance from Cretan mercenaries, and in 404 BC, following the death of Darius, proclaimed himself Pharaoh of Egypt. Although Artaxerxes II, Darius' successor as King of Persia attempted to lead an expedition to retake Egypt he was unable to due to political problems with his brother, Cyrus the Younger. This allowed Amyrtaeus to solidify Egyptian rule over Egypt.
Very little is known about Amyrtaeus' reign. No monuments from this dynasty have been found.
In 398 BC Amyrtaeus was overthrown and executed by Nefaarud I, ending the 28th Dynasty and beginning the 29th Dynasty.