Ezra 4:5

And hired counsellors against them, to frustrate their purpose,
&c.] Either to advise and persuade the king of Persia's officers in those parts not to supply them with money, or to influence the great men at his court to get the edict revoked: and this they did

all the days of Cyrus king of Persia;
who, though the hearty friend and patron of the Jews, yet being engaged in wars abroad with the Lydians and Scythians, and leaving his son as viceroy in his absence, who was no friend unto them, the work went on but slowly, attended with interruptions and discouragements:

even until the reign of Darius king of Persia;
who was Darius Hystaspis, between whom and Cyrus were Cambyses the son of Cyrus, and Smerdis the impostor, who pretended to be Smerdis, the brother of Cambyses; a space of about fifteen years.