Calling a bird of prey from the east,
The man who executes My counsel, from a far country.
Indeed I have spoken it;
I will also bring it to pass.
I have purposed it;
I will also do it. (Isaiah 46:11)
"The man of My purpose" from a far country is "the bird of prey from the east" whom God calls up to execute His plans.
He is also mentioned in "Who has aroused one from the east whom He calls in righteousness to His feet? He delivers up nations before him and subdues kings. He makes them like dust with his sword, as the wind-driven chaff with his bow" (Isaiah 41:2). This person is a future ruler of the Medo-Persian Empire. "Behold, I am going to stir up the Medes against them, who will not value silver or take pleasure in gold" (Isaiah 13:17).
Specifically, God names him. "It is I who says of Cyrus, 'He is My shepherd! And he will perform all My desire.' And he declares of Jerusalem, 'She will be built,' and of the temple, 'Your foundation will be laid'" (Isaiah 44:28). "'I have aroused him in righteousness and I will make all his ways smooth; he will build My city and will let My exiles go free, without any payment or reward,' says the LORD of hosts" (Isaiah 45:13).
At the time Isaiah wrote this, the Assyrian Empire was on the rise. Isaiah spoke of the Babylonians rising to take over and expand the Assyrian Empire. The Babylonians would then be conquered by the Medes who will allow the Israelites to return from captivity and who would finance the rebuilding of Jerusalem and the Temple. Isaiah was written roughly between 742 BC and 701 BC. Cyrus lived from 576 – 530 BC. The edict to allow the Jews to return to Jerusalem was issued in 539 BC. Thus, Isaiah recorded 250 years in advance the name of the future ruler in an empire that would succeed the next empire that would conquer the current empire.
To give some perspective, imagine naming the country that conquers the country that conquers the United States and then name the leader who does it. God does this to prove that He alone is God and rules the universe.
Thanks for the answer.