What are marriage dispensations?
These types of ecclesiastical documents, were granted to couples by a bishop when there were certain impediments that prevented them from contracting a Catholic marriage. Researcher Carmen Paulina Torre Franco explains that “The ordinary form is granted if canonical causes are met, which are twenty-six reasons for which the impediment of kinship can be dispensed.”[1] The most common reasons were consanguinity and affinity.
As part of Catholic canon law, marriage dispensations can be found throughout Latin America. In Mexico, they are very frequent in certain areas where the recurrence of such documents was high, such as the states of Jalisco and Nuevo Leon.
What is consanguinity kinship?
Consanguinity refers to the relationship between two people who share a common ancestor, that is, they have a biological connection through their lineage and family tree.
This type of kinship is determined by the number of generations and ancestors that two people have in common, and is expressed in terms of degrees of kinship, such as first-degree kinship between parents and children, second-degree kinship between siblings, grandparents and grandchildren, and so on.
What is affinity kinship?
Affinity refers to the family relationship established through marriage or common-law union. There is an affinity relationship between a person and their spouse or partner’s relatives, such as parents-in-law, brothers-in-law, sons-in-law, daughters-in-law, and others. This relationship is not based on consanguinity (blood relationship) but on the bond created by marriage or common-law union.
How can marriage dispensations help me in my genealogy?
Marriage dispensations are immensely useful in describing kinship relationships and obtaining valuable and important data such as the names of grandparents, great-grandparents, great-great-grandparents, etc., the names of close relatives such as siblings, uncles, or nieces, places where ancestors lived, and in some cases, discovering what our ancestors did for a living, variations in surnames, ages, among other data.
The format of a marriage dispensation has changed very little over the centuries, but it can be challenging to read and understand the text without a good knowledge of paleography, especially in the handwriting of the 16th and 17th centuries. In short, marriage dispensations are an invaluable resource that can help break down the brick wall in our genealogy.

[1] Torres Franco, Carmen Paulina. (2015). Matrimonio entre parientes. Causas y causales de dispensa en la parroquia de La Encarnación, 1778-1822. Letras históricas, (13), 59-85. Recuperado en 26 de marzo de 2023, de http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S2448-83722015000200059&lng=es&tlng=es.