Daniel 11:5 refers to the "king of the south" (Ptolemy I), one of whose officers would rule a realm greater than his. That officer is Seleucus I.
Daniel 11:6 recounts the episode in which Antiochus II ("the king of the north") married the daughter of Ptolemy II ("the daughter of the king of the south") Berenice/Berenike. But he later when back to his ex-wife Laodice/Laodike I, who then had him, Berenice, and their son assassinated. More on that sad story here.
Daniel 11:7-8 continues the story. Berenice's brother , Ptolemy III (the "branch from her roots") invaded the realm of Antiochus's successor, Seleucus II ("the king of the north," son of Laodice), captured the fortress of Seleucia, and killed Laodice, but he did not conquer the territory.
That takes us to the end of this article. For the first article in an earlier series by the same author about the coinage of the Ptolemaic dynasty, see here and links. It covers some of the same history as this article. And for more on Seleucid coinage, the Seleucid dynasty, and the latter's importance for biblical studies, see here and links.
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