Josephus records that when Alexander the Great arrived to attack Jerusalem, Jaddua the High Priest went out to meet him and showed him a copy of the book of Daniel, wherein Daniel declared that one of the Greeks should destroy the empire of the Persians (Ant. 11.337):
And when the book of Daniel was showed him, wherein Daniel declared that one of the Greeks should destroy the empire of the Persians, he supposed that himself was the person intended; and as he was then glad, he dismissed the multitude for the present, but the next day he called them to him, and bade them ask what favors they pleased of him.
The biblical references where Alexander saw might be Daniel 7:6; 8:3-8, 20-22; 11:3. Alexander supposed that himself was the person intended in the book of Daniel. He was so impressed by this that instead of destroying Jerusalem, so that he entered the city peaceably and worshipped at the Temple.
What does this account tell us? It tells us a very interesting point. The book of Daniel was understood as a prophecy by Josephus. For example, Josephus identifies the reference of the great horn in Daniel 8 as Alexander the Great. He regards Daniel as “one of the greatest prophets,” distinguished by the fact that he not only prophesied future things but fixed the time at which they would come to pass and also prophesied good tidings (Collins, 84). But the book of Daniel does not belong to the Prophets but to the Writings in the Hebrew Bible.
Collins, John J. Daniel. Hermeneia. Minneapolis: Fortress Press, 1993.
Josephus, Flavius ; Whiston, William: The Works of Josephus : Complete and Unabridged. Peabody : Hendrickson, 1996, c1987.