I have read that to explain the absence of the Girgashites in a list of the 7 nations, amora R. Samuel bar Nahman says the Girgashites left Israel and God rewarded them by giving them "Afrike"
"Afrike" sounds a bit like "Africa", a term the Romans used to describe the tops of Tunisia and Libya. The top tip of Tunisia is where Carthage was and is not that hard to see that CarTHage and GirGash look sort of similar.
Is there any Jewish source that more explicitly connects Carthage with the Girgashites? (I am aware that Josephus says Dido, founder of Carthage, was a descendant of Hiram but he could just be telling a made up story and I am also aware that Carthage is otherwise far more historically verifiable than the flight of the Girgashites )