A The purpose and nature of marriage

1   What is marriage?

The Romans considered marriage a partnership, whose primary purpose was to have legiti­mate descendants to whom property, status, and family qualities could be handed down through the generations.

D.23.2.1 (Modestinus): Marriage is the joining of male and female and a partnership for all of life, a sharing of divine and human law.

D.1.1.1.3 (Ulpian): Natural law (ius naturale) is that which nature has taught all animals: for that law is not unique to the human race, but to all animals which arise on the earth or in the sea; and also common to the birds. From this follows the joining of male and female, which we call marriage, from this follows the procreation of children, and their upbringing: for indeed we see also the other animals, even the wild beasts, are thought to have experience of that law.

D.50.16.220.3 (Callistratus): In addition, nature also teaches us that dutiful parents, who take wives with the intention and desire of procreating children, hold by the name of “children” all who descend from us: for we are not able to call our grandchildren by a sweeter name than “children.” For this reason indeed we conceive and bring up sons and daughters, so that from the offspring of our male or female (children) we may leave for ourselves a lasting memorial for all time.

Two aspects of marriage were of particular concern to Roman law and are amply docu­mented in the Digest and other legal sources: consent to the marriage by all parties involved [Part I.C.3 below], and the partners' legal eligibility for marriage with each other [see Chapter 3].

Rules of Ulpian 5.2: Legitimate marriage (iustum matrimonium) occurs, if the right to marry (conubium) exists between those who are contracting marriage, and the male is as mature as the female is capable (sc., of inter­course), and they both consent, if they are legally independent, or their parents also consent if they are in (paternal) power.

Children born in iustum matrimomium received their father's family name (nomen) and were his legal heirs. They also came under his paternal power (patria potestas) until he died or emancipated them — a power which, at least in theory, was all-encompassing and life-long [see Chapter 1, Part II.A].

2    What makes a marriage valid?

Cohabitation and sexual intercourse did not make a marriage, according to the jurists, nor did their absence necessarily imply the absence of marriage:

D.50.17.30 (Ulpian): Sleeping together does not make marriage, but consent does.¹

D.24.1.32.13 (Ulpian): Indeed, if a woman and her husband have lived apart for a long time, but kept the honor of marriage on both sides, which we know sometimes ensues even among consular persons, I think that gifts (between them) are not valid, just as if the marriage has lasted. For sexual intercourse does not make a marriage, but the marital frame of mind (affectio maritalis) does.

Gifts between husband and wife during the marriage were not valid in Roman law [Part I.E]. Thus it was important to determine whether a marriage still existed, and the juristic criterion was whether the couple thought of themselves as being married, even if they lived apart — that is, whether they maintained affectio maritalis toward each other.² “Consular persons” are those who had reached the consulship [see Chapter 1, Part VI.A]. Ulpian may be referring to cases where a provincial governor or other high-ranking official was abroad on government service, and his wife stayed home.

Roman law did not require the performance of any ceremony, religious or secular, for vali­dation of a marriage.

D.23.2.5 (Pomponius): It is agreed that a woman is able to be married to an absent man by means of a letter from him or through his messenger, if she is led into his home. However, it is not possible for a woman who is absent to be led in marriage by a husband by letter or by her own messenger. For there needs to be an escorting into the husband's home, not the wife's, as if into the marital domicile.

D.23.2.6 (Ulpian): Lastly, Cinna writes: It has been replied that the man who took a wife who was absent, and then perished next to the Tiber river as he was returning from dinner, must be mourned by his wife.³

The jurist Gaius pointed out that a marriage, like a mortgage (hypotheca), depended for validity on the consent of both parties, not on written documentation:

D.20.1.4 (Gaius): [the beginning of the passage is omitted here] For written docu­ments are made about these things (mortgages), in order that through them (documents) what has been done can be proved more easily. Even without these, however, what has been done is valid, if there is (unwritten) evidence to prove it.⁴ Just as also a marriage exists, though testimonies (to it) have not been put in writing.

However, there were people in the Empire who thought, following their local customs, that a marriage’s validity required written documentation.

Cod. Just. 5.4.9, 276-282

Emperor Probus Augustus to Fortunatus:

If, with the knowledge of neighbors or others, you had a wife at home “for the sake of producing children,”⁵ and a daughter was begotten from this marriage, though neither marriage tablets nor records pertaining to your daughter's birth were made, nevertheless the truth of the marriage and of the daughter begotten (in it) has its own value.

Cod. Just. 5.4.13, 292-305

Emperors Diocletian and Maximian Augusti and the Caesars to Onesimus:

Documents that were made without marriage (taking place) are not suit­able for proof of marriage if the truth of the matter is otherwise. Nor is a marriage that was lawfully contracted without the introduction of docu­ments invalid, since, even if written documentation has been omitted, other indications of marriage are not invalid.