‘ And Joshua came at that time and cut off the Anakim from the hill country, from Hebron, from Debir, from Anab, and from all the hill country of Judah, and from all the hill country of Israel. Joshua utterly destroyed (devoted) them with their cities. There were none of the Anakim left in the land of the children of Israel, only in Gaza, and in Gath, and in Ashdod did some remain.'
This general statement explains that Joshua and his army also dealt with what was seen as possibly the greatest threat to Israel of all, the feared Anakim. ‘At that time' is vague and simply means some time while he was conquering the land and while he lived. The mention of them shows that some had survived the original attacks on Hebron and Debir and were now resident again there. Also that they were widespread throughout the hill country, possibly acting as mercenary soldiers.
When Israel first moved into the central highlands and took it they would call it ‘the hill country of Israel'. Proud of their conquest they would set their symbol there and claim it for their own. Later when independently minded Judah captured the southern hill country they expressed their semi-independence by calling it ‘the hill country of Judah'. While this was the beginnings of the later split, such a split was not in mind at the time. It was simply a matter of naming two locations with convenient names which expressed possession.
Note the assumption of these verses that ‘the land of the children of Israel' consisted at this stage of the hill countries of Israel and Judah. While enemies outside that had been defeated, their land was not finally possessed. As God had said to Moses, final possession would take place little by little (Exodus 23:29-30).
The Anakim were fierce and very large, formidable fighters, (compare Deuteronomy 1:28; Deuteronomy 2:10; Deuteronomy 2:21; Deuteronomy 9:2) who were mainly settled in the hill country, especially around Hebron (Numbers 13:22). They were seen as in some way related to the mysterious Nephilim (Numbers 13:33) and such a formidable foe that special mention is made of them. It is possible that Arba, as found in Kiriath-Arba, was considered their original ancestor (Joshua 14:15; Joshua 15:13).
It would seem that when Joshua earlier reduced Hebron and Debir (Joshua 10:36-39) and moved on, it was repopulated by those who lived around and those who managed to escape, including the Anakim. Now they had to be ejected again. This second ejection probably refers to what was in fact done by Caleb under Joshua's generalship (Joshua 15:13-19). Some Anakim, however still remained in the strong cities on the coastal plain, (possibly escaping there, but they would always be welcomed as mercenaries) and this is further testimony to the fact that these cities were not seen as taken by Joshua (compare Joshua 13:3). Goliath was probably their descendant.
Anab (Joshua 15:50), a small city which is now a ruin but still called ‘Anab, was eight kilometres (five miles) south of Debir. It is mentioned as Kart-‘anabu in Papyrus Anastasi I and in the Amarna letters.