John Gill Commentary Daniel 8:4

"I saw the ram pushing westward, and northward, and southward; and no beasts could stand before him, neither was there any that could deliver out of his hand; but he did according to his will, and magnified himself." — Daniel 8:4 (ASV)

I saw the ram pushing westward, and northward, and southward ,
&c.] That is, with his horns, as rams do; these kingdoms using all their power and strength, wealth and riches, in fighting with and subduing nations, and pushing on their conquests in all parts here mentioned; to the west, Babylon, Syria, Asia, and part of Greece; to the north, Iberia, Albania, Armenia, Scythia, Colchis, and the inhabitants of the Caspian sea; and to the south, Arabia, Ethiopia, Egypt, and India; all which places were conquered by Cyrus and his successors. No mention is made of the east, because this ram stood in the east, facing the west; and at the right and left were the north and south; and so Cyrus is said to come from the east, (Isaiah 46:11) .

So that no beast might stand before him :
no, not the first beast, the Babylonian monarchy, which fell into the hands of Cyrus; nor any other king or kingdom he and his successors fought against:

neither was there any that could deliver out of his hand ;
or power; Croesus, the rich king of Lydia, and other allies of the king of Babylon, assisted him against Cyrus, and endeavoured to prevent his falling into his hands, but all in vain:

but he did according to his will, and became great ;
none being able to oppose him, he carried his arms where he pleased, and imposed what tribute he thought fit, and obliged them to do whatever was his will; and so became great in power and dignity, in riches and wealth: this monarchy was very large and extensive, and very rich and wealthy, in the times of Cyrus and his successors; and especially in the times of Darius, the last monarch of it, conquered by Alexander, who is described as follows: