Series that aren't a series

(And isn't a publisher series.)

L Sprague de Camp wrote 5 historical novels set in the Hellenic world. They aren't linked except by their setting and historicity (or lack of), but they share a common theme in that they retell various legendary and semi-legendary stories of the Hellenic World with plausible (as of the 1960s) faction.

Would I be justified in grouping them as a series based on their thematic links? I know I could make a list, but I think that sort of misses the point of the links between the books.

The books are:
The Dragon of the Ishtar Gate
The Bronze God of Rhodes
The Arrows of Hercules
An Elephant for Aristotle
The Golden Wind

The Wikipedia article on de Camp describes the five novels as a loosely linked series.

I would consider that a series

My gut feeling, fwiw, says yes.

OK, a new series coming up! One thing is what to call it - Hellenic is wrong (too late), as is Graeco-Roman.

Greek World? All the stories include Greek characters (if not the main protagonist). Perhaps Magna Graecia?

>4 Maddz: De Camp's Greek Tales ?

De Camp's Classical Antiquity Tales?

I would be comfortable calling that a series.

I went for Magna Graecia on the grounds it's about the wider Greek world. The commonality is about the Ancient Greek love of knowledge seeking.