Caput nonum: De Principum Affinitatibus.

The Prince's Marriage and the Common Good

Erasmus argues that princely marriages should serve the commonwealth rather than private ambition, and that public interest must outweigh personal dignity.

In fact, I'd consider it by far the most beneficial arrangement for the commonwealth if the alliances of princes were kept within the kingdom's borders — or if some departure from those borders proved necessary, that they were at least joined only to the nearest neighboring peoples — but to those who are fit to be trusted in friendship. And yet — so they say — a king's daughter shouldn't be married except to a king or a king's son. But those are the attitudes of private citizens — to elevate their own as high as they can — men from whom the prince ought to be utterly removed. Let the prince's sister marry a less powerful man — what of it, if afterward that should prove more advantageous for everyone? And the dignity lost by setting aside a sister's marriage would bring her more honor than if she had preferred a common woman's personal inclination to the public interest.

The Weight of a Prince's Marriage

A prince's marriage, though seemingly private, is in fact a matter of immense public consequence, capable of stirring great upheavals.

A prince's marriage is a private matter of a certain kind, yet we can see that it is almost called the sum of human affairs — so that it very often turns out for us as it once did for the Greeks and Trojans over Helen.¹²

Choosing a Worthy Wife

Erasmus counsels that a prince should select a wife distinguished by virtue rather than noble birth alone.

But if it seems right to make a choice worthy of a prince, let a woman be selected from all the candidates — one commended for her integrity, modesty, and prudence — who would be a fitting wife for the finest of princes, and who would bear him children worthy of both parents and of their fatherland. She is respectable enough by whatever blood she is born, so long as she proves to be a good wife for a good prince.

The Illusion of Dynastic Peace

Erasmus dismantles the popular belief that royal intermarriage guarantees peace, showing instead that such alliances often breed conflict and upheaval.

It's well known that nothing serves the common interest equally well as a prince who deeply loves his people and is in turn loved by them. To this end, the fatherland carries enormous weight, as does a shared likeness of body and mind, along with a certain natural fragrance — a mysterious kinship of spirits that deepens the bond. But a great deal of this is inevitably lost when unequal marriages throw all these things into confusion.³ For it can hardly happen that the fatherland fully embraces those born to it, or that those born to it are wholeheartedly devoted to the fatherland. And yet the common people think of these marriages as if they were unbreakable bonds of public harmony — though experience itself teaches that the greatest upheavals in human affairs arise from precisely this source. Harsh things are complained of: here, some forgotten clause of a betrothal agreement; there, someone takes offense over some matter and leads away another man's bride; one party changes his mind and renounces the prior engagement, then leads a different woman to the altar; another makes some other excuse.⁴⁵ But what do these things have to do with the republic? If dynastic marriages between princes could guarantee peace for the world, I'd wish that all of them were bound together by six hundred alliances. But what good did dynastic marriage do just a few years ago, that James, King of the Scots, should not have invaded the borders of England with hostile forces?⁶ And sometimes it happens that after long years of war and countless disasters, the conflict is finally settled by a marriage alliance — but only after both sides have been worn out by their suffering.

Kinship Cannot Secure Lasting Peace

Erasmus argues that peace founded on kinship is fragile and that dynastic propagation often generates fiercer wars rather than preventing them.

This is what princes must work toward: that a certain lasting peace be joined among all, and that in this they bring their plans together. How could kinship reconcile peace, when it clearly cannot be perpetual?⁷ Once one of the two has died, the bond of harmony is loosened. Because if peace were forged by true reasoning, it would be firm and long-lasting.⁸ But someone might say that this union is made perpetual through the propagation of children.⁹ Then why is war waged most fiercely among those very people who are bound by the closest family ties? On the contrary, it is precisely through this propagation that the exchange of kingdoms arises: the harsh rule of dominion is transferred from one place to another, harshly something yields here, and there it grows — and from these things the gravest upheavals tend to arise.¹⁰ So, for all these reasons, it doesn't turn out that wars are prevented — but it does turn out that fiercer and more frequent ones are stirred up.¹¹

The Human Cost of Dynastic Marriage

Erasmus concludes by showing how dynastic marriages embroil the Christian world in bloodshed, harm the common people, and exile young women, while acknowledging the deep-rootedness of the custom.

For harsh are the kingdoms bound to one another by dynastic marriage; whenever any one person takes offense, he, by right of kinship, stirs up the rest as well, so that from the slightest slight, a great part of the Christian world is immediately moved to arms, and an immense shedding of Christian blood is the price that appeases the temper of a single man. I deliberately refrain from giving examples, lest I offend anyone. In short, through dynastic marriages of this kind, the affairs of princes are perhaps advanced, but the affairs of the people are worn down and afflicted. Furthermore, a good prince does not consider his own affairs to prosper unless the commonwealth's interests are looked after — so as not to say, for now, that along the way the welfare of the young women themselves is not handled very humanely, since they are sometimes banished, as it were, into far-off and remote regions, among men whose language, appearance, customs, and dispositions are utterly unlike their own, when they might have lived more happily among their own people, with somewhat less turmoil. And yet, although I see that this custom is too deeply rooted to hope it can be overthrown, it still seemed right to offer this warning, in case something beyond all hope should by chance come of it.

Read the original Latin

Equidem multo saluberrimum iudicarim Reipublicae, si Principum affinitates intra regni fines continerentur, aut si quid recedendum sit a limitibus, cum proxime finitimis dumtaxat iungerentur, sed iis, qui ad amicitiae fidem sint idonei. Atqui non decet (inquiunt) Regis filiam nisi cum Rege aut Regis filio copulari. At isti priuatorum sunt affectus, suos quantum possint euehere, a quibus oportet Principem alienissimum esse. Minus potenti nubet Principis soror, quid tum postea, si id magis expediat uniuersis? Et illi plus dignitatis adferat neglecta sororii coniugii dignitas, quam si mulierculae affectum publicis commodis praetulisset.

Priuata quaedam res est Principum matrimonium: at hue rerum humanarum summam pene uocari cernimus, ut saepenumero nobis eueniat, quod olim Graecis ac Troianis in Helena.

Quod si placet adhibere delectum Principe dignum, seligatur ex omnibus, integritate, modestia, prudentiaque commendata, quae optimo Principi morigera sit uxor, et illi liberos utroque parente patriaque dignos generet. Satis honesta est quocumque sanguine nata, quae bono Principi bonam praestat uxorem.

Illud in confesso est, nihil aeque expedire in rem omnium, atque ut Princeps uehementer amet suos, et ab iisdem uicissim ametur. Ad quod ingens habet momentum patria, communis corporum et animorum similitudo, et nescio quid natiuae fragrantiae, quam arcana quaedam geniorum affinitas addit: at hinc magna pars pereat oportet, si haec omnia confundant imparia matrimonia. Vix enim fieri potest, ut sic natos, toto pectore agnoscat patria, aut sic nati, toto pectore sint dediti patriae. Et tamen uulgus haec uelut adamantina publicae concordiae uincula putat, cura hinc res ipsa doceat maximos rerum humanarum tumultus exoriri, dura hic queritur ex sponsalium pactis praeteritum nescio quid, hic offensus re quapiam sponsam abducit, ille mutato consilio renunciat priori, et aliam ducit in thalamum, alius aliud quidpiam causatur. Sed quid haec ad Rempublicam? Si Principum inter se affinitas praestaret orbi tranquillitatem, optarem omnes sexcentis affinitatibus esse colligatos. At quid ante paucos annos profuit affinitas, quo minus Iacobus Scotorum Rex infestis copiis inuaderet Angliae fines? Et fit aliquoties, ut post diutinos bellorum tumultus, post innumeras clades, tandem affinitate contracta, res componatur, sed utraque parte iam malis delassata.

Illud agendum Principibus, ut aeterna quaedam pax coeat inter omnes, et in hoc conferant sua consilia. Ut affinitas pacem concilie, certe perpetuam non potest. Altero defuncto, soluitur concordiae uinculum. Quod si ueris rationibus pax conflaretur, ea stabilis esset ac diuturna. Sed dixerit aliquis, liberorum propagatione coniunctionem eam perpetuam reddi. Cur igitur inter hos maxime bellatur, inter quos summa propinquitas est? Immo per hanc propagationem potissimum oritur regnorum commutatio, dura ditionis ius aliunde alio transfertur, dura hinc decedit aliquid, et illic accrescit, quibus ex rebus grauissimi tumultus exoriri solent. Igitur hisce rationibus non fit ne cooriantur bella, sed fit, ut atrociora moueantur et crebriora.

Dura enim regna regnis affinitate connexa sunt, quoties unusquispiam offensus est, is affinitatis iure concitat et caeteros, ut ex qualibet leui offensa, magma pars orbis Christiani statim ad arma moueatur, et immensa Christiani sanguinis factura placatur unius hominis stomachus. Ab exemplis consulto tempero, ne quid offendam quemquam. In summa, huiusmodi affinitatibus, Principum res fortassis augentur, at populi res atteruntur et affliguntur. Caeterum bonus Princeps non aliter iudicat suas res prospere habere, nisi cura Reipublicae commoditatibus consulitur: ut ne dicam interim, quod hac uia non admodum humaniter agitur cura ipsis puellis, quae nonnumquam in procul semotas regiones, ad homines, lingua, specie, moribus, ingeniis dissimillimos, uelut in exsilium relegantur, felicius apud suos uicturae, ut aliquanto minore strepitu. Quamquam autem hanc consuetudinem uideo receptiorem, quam ut sperem posse conuelli, tamen uisum est admonere, si quid forte praeter spem euenerit.

Notes

1 ↩The reading 'hue' (possibly for 'huc,' 'hither / to this point') is uncertain; the translation follows the most plausible sense — that the argument has reached this point in the discussion.
2 ↩The reference to the Greeks, Trojans, and Helen is a classical allusion (the Trojan War), not a scriptural one.
3 ↩nescio quid natiuae fragrantiae: the phrase is deliberately vague — 'a certain native fragrance' — evoking an intangible, almost instinctive quality of kinship rather than a literal scent.
4 ↩uelut adamantina: 'as if adamantine/unbreakable' — the crowd treats these bonds as ironclad, but Erasmus is ironic.
5 ↩praeteritum nescio quid: 'some forgotten/overlooked thing' — deliberately vague, echoing the language of legal grievance.
6 ↩James IV of Scotland (r. 1488–1513) invaded England despite diplomatic ties; he was killed at the Battle of Flodden in 1513. Erasmus wrote this work in 1516.
7 ↩The opening Ut is ambiguous: it could be exclamatory ('How!') or relative/comparative. The rendering takes it as exclamatory, matching the rhetorical force of the section. The form concilie (for expected conciliet) is a manuscript variant; the sense is clearly subjunctive 'may reconcile.'
8 ↩Quod is ambiguous between causal ('because') and relative ('which'). Causal reading chosen as most natural in context. The rare form conflaretur (for expected conflaretur) is retained in sense as 'were to be forged/wrought about.'
9 ↩dixerit is ambiguous between future perfect ('will have said') and potential subjunctive ('might say'). The potential subjunctive reading is preferred as introducing a rhetorical objection.
10 ↩immo functions as an emphatic correction ('on the contrary' / 'nay rather'), pushing back against the previous objection. ditionis is a rare word for dominion or rule. The repeated dura ('harsh') governs both clauses — the transfer of dominion is harsh, and what yields from one side is harsh as well.
11 ↩The impersonal fit ('it happens') is used twice in parallel, first with a negative purpose clause (ne cooriantur bella) and then with a result clause (ut atrociora moueantur et crebriora). The structure is deliberately paradoxical: the very thing meant to prevent war actually produces worse war.

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