Fourth kingdom — This is the kingdom of the Romans, and was to last not only to Christ's first coming, but under antichrist, to his second coming. This did break in pieces all other kingdoms, being too strong for them, and brought all into subjection to it, 'till the stone fell upon it.
Related Commentaries of Daniel 2:40
Daniel 2:40
40 And the fourth kingdom shall be strong as iron: forasmuch as iron breaketh in pieces and subdueth all things: and as iron that breaketh all these, shall it break in pieces and bruise.