Daniel 7:7 (BSB)

After this, as I watched in my vision in the night, suddenly a fourth beast appeared, and it was terrifying—dreadful and extremely strong—with large iron teeth. It devoured and crushed; then it trampled underfoot whatever was left. It was different from all the beasts before it, and it had ten horns.

From Daniel 7. Also in the ESV.

Commentary on Daniel 7:7

• John Calvin (Reformed), Calvin's Commentaries on Daniel 7:7: There is greater difficulty in this Fourth Monarchy. Those who are endued with moderate judgment, confess this vision to be fulfilled in the Roman Empire; but they afterwards disagree, since what is here said of the fourth beast many transfer to the Pope, when it is added a Little Horn sprang up; but. others think the Turkish kingdom is comprehended under the Roman.
• Matthew Henry (Presbyterian), Matthew Henry's Complete Commentary on Daniel 7:1-8: The date of this chapter places it before ch. 5, which was in the last year of Belshazzar, and ch. 6, which was in the first of Darius; for Daniel had those visions in the first year of Belshazzar, when the captivity of the Jews in Babylon was drawing near a period.
• John Gill (Reformed Baptist), Exposition of the Old and New Testaments on Daniel 7:7: After this I saw in the night visions, and behold a fourth beast,.... Not in another night, as Jarchi; but in the same night, and in the same visions of it; only after he had seen the other three successively, then last of all he saw this fourth beast; and more being said of this than of the rest, shows that this was the principal...
• Jamieson-Fausset-Brown (Reformed), Commentary Critical and Explanatory on the Whole Bible on Daniel 7:7: As Daniel lived under the kingdom of the first beast, and therefore needed not to describe it, and as the second and third are described fully in the second part of the book, the chief emphasis falls on the fourth. Also prophecy most dwells on the end, which is the consummation of the preceding series of events.