Authors: Klearchos of Soloi, Lives, book 4, as cited by Athenaios of Naukratis, Sophists at Dinner 12.23-24 = 522d-523b (link to Greek text and full translation).
Comments: Athenaios cites Klearchos (or: Clearchus) of Soloi on two different stories about peoples in southern Italy engaged in luxury and disrespectful behaviour: the people of Tarentum and the Iapygians themselves (the victims become perpetrators). It seems that book four of Lives cited a variety of ethnic groups as negative examples of peoples who engaged in violent abuse and/or luxury. A final example from Iberia is briefly offered, involving luxury supposedly leading to effeminacy.
Source of the translation: C.B. Gulick, Athenaeus: The Deipnosophists, volume 5, LCL (Cambridge, MA: HUP, 1933), public domain (copyright expired), adapted by Harland.
[People of Tarentum]
In the fourth book of his Lives, Klearchos says that after the Tarentinians [people of Tarentum in southern Italy] had acquired strength and power, they progressed to such a point of luxury that they made the sking on their entire bodies smooth and so began this practice of removing hair among all other peoples. All the men, he says, wore a transparent cloak with purple border, garments which today are fashionable among women. But later, blindly led by luxury into violently disrespectful behaviour (hybris), they uprooted Carbina, a city of the Iapygians. They made the boys, girls, and women in their prime gather in the temples of Carbina and created a spectacle, exposing their bodies naked for all to gaze during the day. Anyone who wanted, leaping like wolves upon a herd into this wretched group, could feast his lust on the beauty of the victims gathered there. Yet while everyone was watching, they hardly suspected that the gods were watching most of all. For a lower deity (daimonion) was so angry that it blasted all the Tarentinians who had committed this lawlessness in Carbina. Even today, each of the houses in Tarentum has as many columns outside the front doors as it harboured members of the group dispatched to Iapygia. On the anniversary of their destruction, the people neither make lamentation for the dead nor pour the customary libations in their honour, but sacrifice to Zeus the Thunderer (Kataibatēs) at these columns.
So, to continue, the Iapygians are a descent group (genos) from Krete who had come to look for Glaukos and settled there. But their successors, forgetting the Kretan discipline of life, went so far into luxury and then later into disrespectful behaviour (hybris) that they became the first to rub cosmetics on their faces and assume false fronts attached to their hair. While they wore brightly-coloured robes, they regarded working and toiling at a trade as too disgraceful. Most of them made their houses more beautiful than temples. The leaders of the Iapygians, in utter contempt for the deity, looted the statues of the gods from the temples, telling them to go elsewhere. For this reason, they were struck from the heavens with fire and copper and handed on this story. Copper specimens of the missiles from the sky were shown as evidence for a long time afterwards. All the survivors from those times to the present day live with hair close-cropped, dressed in mourning garb, and lacking all the good things they had formerly enjoyed.
[Iberians and Massilians]
As for the Iberians, though they proceed in elaborately decorated robes and wear tunics reaching down to the feet, they are not at all impeded in the strength they display in war. But the people of Massilia [a Greek colony], who wore the same fashion of clothing as the Iberians, became effeminate. At any rate, their behaviour is indecent because of the weakness of their souls, and they are effeminate through luxury. This is where the current proverb comes from: “May you sail to Massilia!”