In the second chapter of Daniel, starting at verse 31, Daniel begins to describe a dream that Nebuchadnezzar, king of Babylonia, had dreamed the contents of which he had kept secret.
The dream was of a statue the head of which was of gold, the breasts and arms of which were of silver, the belly and thighs of which were of bronze, the legs of which were of iron, and the toes of which were of iron and clay.
Daniel told Nebuchadnezzar that the head of gold represented that very king of Babylonia - Nebuchadnezzar. Daniel tells him that the other parts of the statue stand for kingdoms that would follow his - but, not the names of those kingdoms.
The Medes and Persians were the peoples of the kingdom that succeeded Babylonia; and, the two-part nature of that kingdom is agreeable with the interpretation that the silver arms and breasts of the statue represented that kingdom.
The Greeks, as a unified people, succeeded the Persians and, later, divided into two main parts - the Ptolemaic Egyptian and the Seleucid Syrian. The unified nature of the Greek empire at its beginning (i.e., under Alexander the Great) followed by the dividing of that empire is agreeable to the interpretation that the belly and thighs of the statue represent Greece.
The next part of the statue is made of iron. They are two legs that begin and end apart from each other. Many interpreters want to make Rome the nation represented by those legs. However, The people of Rome do not fit as a kingdom with two separate expressions both of which begin at the very time the Greek empire collapses. But there is a people who do.
When Nebuchadnezzar was king of Babylon, he overran Jerusalem and took Jehoiachin, king of the Jews, to Babylonia as a captive. He left Zedekiah king in Jehoiachin's place. Later, Zedekiah made overtures of allegiance to Egypt, and Nebuchadnezzar had Zedekiah's sons executed - and Zedekiah's eyes were gouged out.
After about 30 years of captivity, Nebuchadnezzar's successor brought Jehoiachin out of prison, and made him high king over all the other kings of the great international trade cartel for which Babylonia was famous. (It reminds me of the way Pharaoh brought Joseph out of prison to make him number 2 in Egypt. Did Jehoiachin ride the coattails of Daniel's genius?)
So, Jehoiachin became a king in Babylonia and his offspring carried on a dynasty, of sorts, as ethnarchs, there, for a very long time. During the days of Cyrus, Jews had such great prominence in the kingdom that they could have had Cyrus to fund they're return to Jerusalem. During the days of Esther, the Jews had such power under the Persians that many gentiles joined the Jewish religion just to keep from being killed by Jews.
At the end of the captivity, many Jews went back to Judea. They remained under the rule of the Persians until the Greeks defeated Persia. Naturally, it followed that the Jews in, both, Babylonia and Judea, continued under the power of the Greeks.
That changed when the Jews of Jerusalem, under the Maccabees, rose up against the Syrian Greeks, and cast off that yoke. All at once, you had two separate populations of the Jewish people free to rule in separate parts of the world; and, the Maccabees reigned in Jerusalem while the ethnarchs in Babylonia ruled the Jews, there.
Rome didn't even touch the area until much later. In fact, it wasn't until the eighth Maccabean monarch was in position that Marc Antony came and ended that dynasty.
So, it looks, to me, like the legs of iron are made up of the Jews under the Jewish authorities in Jerusalem and Babylonia.
That might indicate that the toes of iron and clay are 10 Caesars: Julius, Augustus, Tiberius, Caligula, Claudius, Nero, Galba, Otho, Vitellius, and Vespasian.