From Theodor Mommsen (trans. William P. Dickson) History of Rome, Vol. 4 (London 1867), Book 5, Chapter 7, pp. 286-87 (link here)
Mind you, an edition of this work won a fucking Nobel Prize for Literature in 1902
In the mighty vortex of the world’s history, which inexorably crushes all peoples that are not as hard and as flexible as steel, such a nation could not permanently maintain itself ; with reason the Celts of the continent suffered the same fate at the hands of the Romans, as their kinsmen in Ireland suffer down to our own day at the hands of the Saxons — the fate of becoming merged as a leaven of future development in a politically superior nationality. On the eve of parting from this remarkable nation we may be allowed to call attention to the fact, that in the accounts of the ancients as to the Celts on the Loire and Seine we find almost every one of the characteristic traits which we are accustomed to recognize as marking the Irish. Every feature reappears : the laziness in the culture of the fields ; the delight in tippling and brawling ; the ostentation… ; the language full of comparisons and hyperboles, of allusions and quaint turns; the droll humour … ; the hearty delight in singing and reciting the deeds of past ages, and the most decided talent for rhetoric and poetry ; the curiosity … and the extravagant credulity which acted on such accounts, for which reason in the better regulated cantons travellers were prohibited on pain of severe punishment from communicating unauthenticated reports to others than the public magistrates ; the childlike piety, which sees in the priest a father and asks him for his advice in all things; the unsurpassed fervour of national feeling, and the closeness with which those who are fellow-countrymen cling together almost like one family in opposition to the stranger; the inclination to rise in revolt under the first chance leader that presents himself and to form bands, but at the same time the utter incapacity to preserve a self-reliant courage equally remote from presumption and from pusillanimity, to perceive the right time for waiting and for striking, to attain or even barely to tolerate any organization, any sort of fixed military or political discipline. It is, and remains, at all times and places the same indolent and poetical, irresolute and fervid, inquisitive, credulous, amiable, clever, but — in a political point of view — thoroughly useless nation ; and therefore its fate has been always and everywhere the same.