WHAT DANIEL REFERS TO.
Some may think this prophecy refers to the establishing of the kingdom of heaven on earth in the days of Christ's first coming. This cannot be the case. God's kingdom at that time did not "break in pieces and consume" the one great kingdom then existing—the Roman empire. On the other hand the worldly powers, which St. John describes as a "beast," made "war with the saints," and overcame them, and got power over all kindreds, and tongues and nations. (Revelation 13: 7).
The kingdom referred to by Daniel, as he plainly says "shall not be left to other people," while the Gospel of the kingdom in the days of Christ's former Apostles was rejected by the Jews and left to other people. It was taken to the Gentiles.