A strong king: Alexander. (Challoner) — The sequel clearly points him out. Before fifteen years had elapsed, his mother, brother, and children were slain. Arideus, his brother, was declared regent till it should be seen what Roxana should bring forth. After the death of those who might be heirs of Alexander, four generals took the title of kings. Others governed in different places, but were destroyed by degrees.

Matthew Henry Commentary on the Whole Bible (Concise) (Matthew Henry)

Verses 1-30 The angel shows Daniel the succession of the Persian and Grecian empires. The kings of Egypt and Syria are noticed: Judea was between their dominions, and affected by their contests. From ver. ( 5-30 ) , is generally considered to relate to the events which came to pass during the continuance of these governments; and from ver. ( 21 ) , to relate to Antiochus Epiphanes, who was a cruel and violent persecutor of the Jews. See what decaying, perishing things worldly pomp and possessions are, and the power by which they are gotten. God, in his providence, sets up one, and pulls down another, as he pleases. This world is full of wars and fightings, which come from men's lusts. All changes and revolutions of states and kingdoms, and every event, are plainly and perfectly foreseen by God. No word of God shall fall to the ground; but what he has designed, what he has declared, shall infallibly come to pass. While the potsherds of the earth strive with each other, they prevail and are prevailed against, deceive and are deceived; but those who know God will trust in him, and he will enable them to stand their ground, bear their cross, and maintain their conflict.