The interpretation of Daniel 7 can be a bit perplexing. I thought I would attempt a quick and hopefully simple breakdown of Daniels four beasts that rise from the sea. It will aid in the interpretation of the beast kingdom in Revelation 13, and 17, and perhaps offer some clarity concerning the rise of this kingdom in the latter days.
The writing below is based upon scripture as the Bible is interconnecting: scripture defines scripture. Daniels night vision interconnects with Nebuchadnezzar's dream in Daniel 2. Nebuchadnezzar was intensely occupied with the future of the mighty kingdom he had built. The Bible doesn't require outside sources to interpret scripture but, we often find that historical events fill in the gaps.
God doesn't want us confused, he wants us to understand what the prophets are documenting. Fortunately for us, there was an angel close by to give us an explanation, adding clarification to what Daniel was witnessing.... the angel told Daniel:
Daniel 7:23,24 The fourth beast will be a fourth kingdom on the earth, which will be different from all the other kingdoms and will devour the whole earth and tread it down and crush it. Out of this kingdom ten kings will arise; and another will arise after them and he will be different from the previous ones and will subdue three kings.