ASK FATHER: Uncle married his niece… is that okay?

From a reader…

My mother in law married her much older uncle after abandoning her children. Why does the Catholic Church approve of this?

Hang on.  Before you make all sorts of assumptions, let’s drill in.

The Code of Canon Law is clear, except where it isn’t.

Canon 1091 establishes that marriage is invalid between persons related in the direct line and in the collateral line up to and including the fourth degree. Canon 1078 declares that dispensations are never given for marriage in the direct line or the second degree of the collateral line. There. That clears it up. So, much for your accusation.

Holy Church has long been interested in parsing the family tree for marriage purposes. Early in the life of the Church, we faced a world where incest was rife. The famous Cleopatra (Cleopatra VII) was married, sequentially, to her two brothers, Ptolemy XIII and XIV, before putting the moves on Julius Ceasar. On the Roman side of things, I, Claudius is a good place to start in trying to figure out the complexities of marriage and family in the Roman upper classes. To all of this, the Church, drawing on Her Jewish roots and divine revelation, said, “Hold on a minu

Breaking relations in consanguinity (blood relations) and affinity (relatives by marriage) and then into the direct line (grandparent, parent, child, grandchild) and the collateral line (sibling, aunt, uncle, cousin), the Church has always forbidden marriage between those related in the direct line, no matter how many degrees (generations) separate them. In the collateral line, degrees have been counted in different manners. Today, the best way to count degrees is to count up the relatives and subtract the common ancestor – thus a brother and sister are in the second degree of consanguinity – brother, sister, parent, minus the parent gives us two. Cousins are in the fourth degree – cousin, cousin, parent, uncle, grandparent, minus the grandparent. Uncle and niece are in the third degree – niece, parent, uncle, grandparent, minus grandparent.

Now, the Church is clear that the prohibition of marriage in the direct line is divine law – the divine law is not dispensed. In the collateral line, especially beyond the second degree, it’s understood that this is ecclesiastical law, and therefore subject to a possible dispensation.

On occasion, in those jurisdictions where it is civilly legal, I have heard of cases of bishops dispensing from the prohibition against the fourth degree of consanguinity – first cousins marrying. Usually, care is taken to make sure that there is no danger of children being born with debilitating birth defects, and that the marriage will not cause problems in the family or scandal among the faithful. I can’t say that I have ever heard of a bishop dispensing from the impediment of consanguinity in the third degree. It’s difficult to comment on a situation without knowing all the particulars, but this situation certainly does seem highly unusual. Ask either the priest who married this couple, or the local bishop for clarification.

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  1. Justalurkingfool says:

    Based upon what I was told. I had a great Uncle and a great Aunt who were first cousins and were given a dispensation to marry. There were no children from their relationship. I remember both of them, although I was quite young, in single digits, when my great Uncle died.


  2. majuscule says:

    Some of us doing genealogical research are blessed that the church kept these records. I’m able to access digital images online (sometimes going back to the 1600s) of my Catholic ancestors of a certain ethnicity.

    If they were granted a dispensation for consanguinity or affinity it is stated in the wedding record, as well as the degree. Sometimes this enables the researcher to figure out how the couple was related–adding another line to the family tree. (I think the degree in those times was, as you state, counted differently because I have ancestors related in the second and third degree of that time who were dispensed.)

    Thank goodness for our church records!

  3. TWF says:

    Is this an uncle by blood or by marriage? I assume a dispensation would still be required, but it would seem less…unsettling…if the niece had, say, married a widowed “uncle” who had been married to the niece’s biological aunt.

  4. Bene actum. Delectes nos porro. Multum te laudo. Sincere loquor . . . Hoc est magni momenti.

  5. Suburbanbanshee says:

    A lot of the kings and queens of Aragon, Castile, Portugal, et al, were related.So it was pretty common for the royal families to apply for dispensations when marrying cousins.

    The time when an uncle married a niece, they did not even bother to apply. They just married illicitly, had sex, had kids, and then separated after ten years and several royal heirs. The niece went to a convent, the uncle did not marry again, and they submitted repentance paperwork to Rome, asking for the kids not to be penalized. It was pretty barefaced.

  6. Tinidril says:

    My parents are first cousins; my mother’s mother and my father’s father were brother and sister. They did not meet til they were adults (my father was born in Ireland, and my mother was born in the U.S.). They got *2* dispensations…one to marry as first cousins and one for a secret wedding, because they knew the family would go nuts. I believe the grounds for the dispensation was the risk that they’d marry outside the Church. The state we live in permits first cousin marriages but not all do. They had 7 kids, all healthy. The only anomaly is that several of us developed in adulthood some interesting cardiac issues that my cardiologist says are sometimes seen in cousin marriages. Oh, and all the daughters are shorter than my mother, who was rather a tall woman. But my brothers are all taller than my father, so maybe that’s nothing.

    I don’t know if this is true or not, but I was told that children and grandchildren of a first cousin marriage can’t get a dispensation to marry…that there has to be a gap of a couple of generations. There probably isn’t any law against it, at least in places where it’s already legal for first cousins to marry.

    Any mental issues were already present in relatives who *didn’t* marry each other. ;-)

  7. Tinidril says:

    I should have said “can’t get a dispensation to marry a first cousin” in the second paragraph

  8. Pigeon says:

    Where did this leave Woody Allen?

  9. I guess a bishop might grant a dispensation for an uncle-niece union in a royal-family-type situation where there are compelling dynastic considerations. That’s the only example I can think of off the top of my head where that might happen.

  10. Geoffrey says:

    In 1760, D. Maria Francisca Isabel Josefa Antónia Gertrudes Rita Joana de Bragança, Princess of Brazil, Duchess of Bragança, and heir presumptive to the Crown of Portugal married her uncle, the younger brother of her father D. José I.

    She was 25 and her uncle / husband was 42. Apparently they had a happy marriage and had six children that survived into adulthood. She would later succeed her father as D. Maria I, Queen of Portugal, and her husband (and uncle) would become D. Pedro III, King of Portugal “iure uxoris”.

    I would assume that they received the necessary dispensations directly from the Holy See.

  11. WmHesch says:

    Medieval law forbade marriages to the 7th degree of consanguinity inclusive… Imagine how difficult it was to find an eligible spouse in smaller towns and villages

  12. Andrew_81 says:

    Majescule :

    You’re right. Before the 1983 Code, the Germanic way of counting degrees was used. In 1983 this changed to the much simpler Roman method.

    In the Roman (current) method you make a chart, count up the line to the common ancestor, then down the other side, counting the gaps between people. Brother to sister is 2nd degree (and never dispensed); aunt/uncle to niece/nephew is 3rd degree; first cousins are 4th degree; first cousins, once removed are 5th degree; and second cousins are 6th degree. The impediment is to the 4th Roman degree, but can be dispensed in the 3rd and 4th degree. A 3rd degree dispensation is probably rare, except in odd cases. One I could think of would be in a large family with a wide age spread where the uncle is the youngest of his siblings and the niece is the oldest daughter of the uncle’s oldest brother. Thus, they are relatively close in age. Add to that some fairly grave reason (e.g. a child), and it’s possible. It would not be dispensed if local civil law prohibited it.

    In the older Germanic method you counted by generations. So brother and sister were 1st degree, first cousins were 2nd degree, and second cousins were 3rd degree. If one side were lopsided, you took the longer side. The impediment was at the 3rd degree, but at this level was considered minor, so always dispensed. At the 2nd degree it was dispensed with some difficulty (grave reason). 1st degree (brother & sister) was never dispensed.

    The 1983 Code made the computation simpler and removed an impediment to a degree which was always dispensed.

    That’s why you may see 2nd and 3rd degree relations in your ancestry. If it’s from before 1983 that means they are first cousins (2nd degree); Uncle/aunt to niece/nephew (2nd degree); first cousins, once removed (3rd degree) or second cousins (3rd degree).

    Clear as mud … ?

  13. defreitas says:

    The Portuguese example is absolutely true, they had a good marriage, except that she went mad after he died. There was also an attempt at another uncle / niece marriage in the 19th century. It was part of a dynastic settlement between a son of Maria I and Pedro III, Miguel I and his niece Maria da Gloria, but he reneged on the deal and the Portuguese civil war broke out. I also think there was a wedding in the 17th century between a Holy Roman Emperor and his niece, and King Philip II of Spain married his niece Anna of Austria. The was so much inter breeding within the Hapsburg family at one time that the Spanish branch actually collapsed because of severe physical deformities of Charles II. My parents were the children of cousins, a paternal grandmother and a maternal grandfather were brother and sister, but they still had to receive a dispensation to get married.

  14. a catechist says:

    It will hardly be believed, but…the town of Salaparuta in central Sicily (destroyed by earthquake and not on most maps) had a population who overwhelmingly had the same last name : Graffagnino. They kept excellent family records for this reason & after the most recent destruction of the town, the parish priest became the chief historian & geneaologist. The towns folk had elaborate naming customs (which male child got named after which male ancestor/relative) and it seems to have developed as a way to keep track of how they were related. Anyway, a number of people from Salaparuta settled in New Orleans in the late 19th cent. & two of my ancestors, both named Graffagnino, were denied marriage until the pastor in the Old Country wrote to their pastor explaining that they were not related within the forbidden degrees of consanguinity. Everyone, priests and laity, seems to have taken this VERY seriously in an anomalous situation. It’s thought that all Graffagninos in the U.S. are descended from Salaparuta, though a few moved Tripani a while before immigrating.

  15. servus humilis says:

    King Charles II of Spain in his direct ancestry had two instances of uncles marrying nieces (and one was a niece-cousin). Hence he suffered from multiple physical defects, including, apparently, impotence and was the last Hapsburg king of Spain.

    King Louis XIV married his twice-first cousin (brother-sister married brother-sister) and only one child lived to adulthood, and he (the Grand Dauphin) would be entertained for hours tapping his boot with his cane.

    All of this in-breeding was with proper Church dispensations. The good news is that the Church has learned from these manifest errors and would never issue such dispensations again.

  16. Maltese says:

    Hitler’s parents (first cousins) got a dispensation from the Pope to marry. That worked out really well!

  17. majuscule says:


    Your explanation of the difference between the Germanic and Roman ways of counting degrees (that you thought might be “clear as mud”) makes more sense than an explanation I read in a genealogy forum. Thanks for that!

  18. Absit invidia says:

    Ay caramba! This just spells out yet another case for the celibate religious life.

  19. cwillia1 says:

    There is a theory, by whom I forget, that the strictness of the medieval church with respect to incest helped to break down clan loyalties and create national identities in Europe. This is in contrast to the Islamic custom of cousin marriage within the clan (man marries father’s brother’s daughter). All sorts of consequences flow from exogamy versus endogamy according to this theory.

  20. Cafea Fruor says:

    Tindril, what you said about the children and grandchildren from a marriage between first cousins not being able to marry their first cousins is correct. I used to work in the diocesan office that handled marriage dispensations, and this question did come up once. The Vicar General explained that if someone wanted to marry a first cousin, it can be done, but there’d be all sorts of checking to make sure that it hasn’t happened for several generations for the sake of making sure any children from the marriage aren’t at risk for genetic problems. I asked why this is even a question anymore, since people tend to balk at the idea of marrying a cousin, and was given the answer that we tend to forget that the country/culture we live in is not the only one out there. Apparently, in certain countries where the Christian population is very small, marrying cousins happens a little more often. Let’s say there’s a Catholic woman living in a Muslim country with such a small Catholic population that her only viable options are to marry her Catholic uncle or marry a Muslim man. It may be that if she couldn’t marry her uncle, she’d marry outside the faith instead of remaining single. After all, being an unmarried woman in a Muslim-majority country can be very challenging, if not dangerous, and maybe she’s widowed and has a couple of young kids and can’t even think about something like religious life. So I think there’s a preference to give dispensation for marrying a not-so-distant relative who’s Catholic or at least Christian (a sacramental marriage) over giving a dispensation disparity of cult (a non-sacramental marriage), as long as it’s been checked that there weren’t other close-relative marriages in her direct line within a few generations, to minimize the risk of birth defects, etc.

  21. Ellen says:

    Queen Victoria and Prince Albert were first cousins. Queen Elizabeth and Prince Philip are third cousins. I’ll have to admit the idea of cousin marriage makes me squirm. In my state it is illegal to marry your first cousin.

  22. cathgrl says:

    I come from a rural area in eastern Michigan where several German-speaking families from Alsace-Lorraine, Germany, etc. settled in the mid-1850s. A couple of generations later, a set of first cousins wanted to marry. The Priest wouldn’t marry them, the story goes, so they went to Canada to get married. They had several children, but it seems no unusual problems with the children. One of them became village president.

  23. Poor Yorek says:

    Fictional, of course, but Edmund Bertram and Fanny Price are first cousins who marry in Jane Austen’s Mansfield Park with not so much as a raised eyebrow (insofar as being cousins, that is).

    Charles Darwin married his first cousin, Emma.

  24. Imrahil says:

    It may be of note that while certain results tend to appear from inbreeding – which are, I hear, far less in first cousins (unless perhaps double first cousins; Edward VII was not an imbecile) than in siblings; Edward – that did not enter at all into the semi-official explanation St. Thomas gives for the impediment of consanguinity.

    The secondary essential end of marriage is the curbing of concupiscence; and this end would be forfeit if a man could marry any blood-relation, since a wide scope would be afforded to concupiscence if those who have to live together in the same house were not forbidden to be mated in the flesh. Wherefore the Divine law debars from marriage not only father and mother, but also other kinsfolk who have to live in close intimacy with one another and ought to safeguard one another’s modesty.

    But the accidental end of marriage is the binding together of mankind and the extension of friendship: for a husband regards his wife’s kindred as his own. Hence it would be prejudicial to this extension of friendship if a man could take a woman of his kindred to wife since no new friendship would accrue to anyone from such a marriage. Wherefore, according to human law and the ordinances of the Church, several degrees of consanguinity are debarred from marriage.
    (Sth. Supp. 54 III)

    In brief words: 1. Keep the family, apart from of course the spouses that make up the family, a sex-free zone (not a place where to look for spouses). 2. Multiply the familial bonds there are between people: “oh, pity we were never introduced, but as a matter of fact you’re the wife of my cousin’s wife’s cousin.” (Around here, at least nowadays that would automatically be followed by the two relations immediately “thouing” each other, addressing one another in 2nd person singular rather than 3rd person plural). And then maybe 3. do something against genetic diseases, which St. Thomas thought sufficiently unimportant to not talk about it at all.

  25. defreitas says:

    Queen Victoria and Prince Albert were first cousins, and though none of her children were imbeciles, she did have a son with hemophilia. She was quite angry with the doctors because she said “this was not a disease that was found in her family”. I wonder if they pointed out that her own marriage was the cause of the condition. It was through her lineage that members of the German, Russian, and Spanish Royal families were afflicted with the condition. Of course, Queen Victoria being head of the Church of England (or governor or what), would not have had to ask for a Papal dispensation.

  26. spock says:


    Or as Father Z might say, “Blech”.

  27. leftycbd says:

    Wait a minute. Doesn’t the original poster state that this woman married her uncle after abandoning her children? Perhaps this whole discussion is moot depending on the details of this situation. For example, did she abandon her first husband too? Was this first marriage valid? Did the church know about said children at the time of the marriage to her uncle?

  28. Imrahil says:

    Dear defreitas,

    as far as I know, scientists assume the hemophilia came from a spontaneous mutation in Queen Victoria herself, or possibly a not too distant ancestor, which would have been passed on or not passed on no matter who the husband was.

  29. Jesson says:

    In 1932, Archbishop Michael O’Doherty of Manila requested the Holy See (1) to restore the old dispensation granted to the natives of the Philippines to contract matrimony within the third collateral line of consanguinity (granted by Paul III’s “Altitudo” and subsequently abolished by Leo XIII’s “Trans Oceanum”); and (2) to issue a blanket “sanatio in radice” for all those matrimonies contracted in the interim between the expiration of the original dispensation and its subsequent restoration.

    Both requests were granted.

    See:, pp xxi-xxii

  30. j says:

    There’s a Country Song for this (nobody doubted there was)
    I’m My Own Grandpa- Ray Stevens

  31. Volanges says:

    My parents were first cousins or perhaps half-first cousins? They shared a grandmother. My paternal grandfather’s mother was widowed young enough to remarry and bear two more children. One of those children became my maternal grandmother. So in this case the children of half siblings married.

    At first the bishop refused to give a dispensation for their marriage. We don’t know exactly why but my father thought it might have had something to do with the congenital hip problem my mother had. At any rate, the parish priest, for whom my 38 year old dad has served Mass for 26 years, went to bat for them. In the end the bishop consented to the dispensation. My two brothers and I have no sign of the congenital disorder Mom had.

    I hadn’t realized how close their kinship was until the parish published the sacramental and death records up to 1920. That’s when I started researching my family tree and discovered the relationship. It had never been hidden, as the great-grandmother’s name appeared in our baby books. We had simply never stopped to think of what it meant.

    One of the parishes in our diocese is isolated, on an island. The marriage register for that parish reveals that almost every marriage celebrated there involves a dispensation for consanguinity. It’s no surprise that most of the residents of that parish are short and have that certain look that allows you to recognize them at a glance.

  32. un-ionized says:

    Volanges, second cousins?

  33. KateD says:

    There are 7.12 billion people on the planet. Why do we even need dispensations for consanguinity? Give an applicant a plane ticket, instead….better than encouraging them to dive into the shallow end of the gene pool. Sheesh….

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