Several genealogical numbering systems have been widely adopted for presenting
family tree
A family tree, also called a genealogy or a pedigree chart, is a chart representing family relationships in a conventional tree structure. More detailed family trees, used in medicine and social work, are known as genograms.
Representations of ...
s and
pedigree chart
A pedigree chart is a diagram that shows the occurrence and appearance of phenotypes of a particular gene or organism and its ancestors from one generation to the next, most commonly humans, show dogs, and race horses.
Definition
The word pedigree ...
s in text format. Among the most popular numbering systems are:
Ahnentafel
An ''ahnentafel'' (German for "ancestor table"; ) or ''ahnenreihe'' ("ancestor series"; ) is a genealogical numbering system for listing a person's direct ancestors in a fixed sequence of ascent. The subject (or proband) of the ahnentafel is li ...
(Sosa-Stradonitz Method), and the Register, NGSQ, Henry, d'Aboville, Meurgey de Tupigny, and de Villiers/Pama Systems .
Ascending numbering systems
Ahnentafel
Ahnentafel
An ''ahnentafel'' (German for "ancestor table"; ) or ''ahnenreihe'' ("ancestor series"; ) is a genealogical numbering system for listing a person's direct ancestors in a fixed sequence of ascent. The subject (or proband) of the ahnentafel is li ...
, also known as the Eytzinger Method, Sosa Method, and Sosa-Stradonitz Method, allows for the numbering of ancestors beginning with a descendant. This system allows one to derive an ancestor's number without compiling the complete list, and allows one to derive an ancestor's relationship based on their number. The number of a person's father is twice their own number, and the number of a person's mother is twice their own, plus one. For instance, if John Smith is 10, his father is 20, and his mother is 21.
In order to readily have the generation stated for a certain person, the Ahnentafel numbering may be preceded by the generation. This method's usefulness becomes apparent when applied further back in the generations: e.g. ''08-146'', is a male preceding the subject by 7 (8-1) generations. This ancestor was the father of a woman (146/2=73) (in the genealogical line of the subject), who was the mother of a man (73/2=36.5), further down the line the father of a man (36/2=18), father of a woman (18/2=9), mother of a man (9/2=4.5), father of the subject's father (4/2=2). Hence, ''08-146'' is the subject's father's father's mother's father's father's mother's father.
The atree or Binary Ahnentafel method is based on the same numbering of nodes, but first converts the numbers to binary notation and then converts each 0 to M (for Male) and each 1 to F (for Female). The first character of each code (shown as X in the table below) is M if the subject is male and F if the subject is female. For example 5 becomes 101 and then FMF (or MMF if the subject is male). An advantage of this system is easier understanding of the genealogical path.
The first 15 codes in each system, identifying individuals in four generations, are as follows:
Surname methods
Genealogical writers sometimes choose to present ancestral lines by carrying back individuals with their spouses or single families generation by generation. The siblings of the individual or individuals studied may or may not be named for each family. This method is most popular in simplified single surname studies, however, allied surnames of major family branches may be carried back as well. In general, numbers are assigned only to the primary individual studied in each generation.Curran, Joan Ferris. ''Numbering Your Genealogy: Sound and Simple Systems.'' Arlington, Virginia: National Genealogical Society, 1992.
Descending numbering systems
Register System
The Register System uses both common numerals (1, 2, 3, 4) and
Roman numerals
Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers are written with combinations of letters from the Latin alphabet, eac ...
(i, ii, iii, iv). The system is organized by generation, i.e., generations are grouped separately.
The system was created in 1870 for use in the ''New England Historical and Genealogical Register'' published by the
New England Historic Genealogical Society
The New England Historic Genealogical Society (NEHGS) is the oldest and largest genealogical society in the United States, founded in 1845.
NEHGS provides family history services through its staff, original scholarship, website,Boston, Massachusetts. ''Register Style'', of which the numbering system is part, is one of two major styles used in the U.S. for compiling descending genealogies. (The other being the NGSQ System.)Curran, Joan Ferris, Madilyn Coen Crane, and John H. Wray.''Numbering Your Genealogy: Basic Systems, Complex Families, and International Kin.'' Arlington, Virginia: National Genealogical Society, 1999.
(–''Generation One''–)
1 Progenitor
2 i Child
ii Child (no progeny)
iii Child (no progeny)
3 iv Child
(–''Generation Two''–)
2 Child
i Grandchild (no progeny)
ii Grandchild (no progeny)
3 Child
4 i Grandchild
(–''Generation Three''–)
4 Grandchild
5 i Great-grandchild
ii Great-grandchild (no progeny)
6 iii Great-grandchild
7 iv Great-grandchild
NGSQ System
The NGSQ System gets its name from the ''National Genealogical Society Quarterly'' published by the
National Genealogical Society The National Genealogical Society (NGS) is a genealogical interest group founded in 1903 in Washington, D.C. with over 10,000 members. Its headquarters are in Falls Church, Virginia. The goals of the organization are to promote genealogical skill ...
headquartered in
Falls Church, Virginia
Falls Church is an independent city (United States), independent city in the Commonwealth (U.S. state), Commonwealth of Virginia. As of the 2020 United States Census, 2020 census, the population was 14,658. Falls Church is included in the Wash ...
, which uses the method in its articles. It is sometimes called the "Record System" or the "Modified Register System" because it derives from the Register System. The most significant difference between the NGSQ and the Register Systems is in the method of numbering for children who are not carried forward into future generations: The NGSQ System assigns a number to every child, whether or not that child is known to have progeny, and the Register System does not. Other differences between the two systems are mostly stylistic.
(–''Generation One''–)
1 Progenitor
+ 2 i Child
3 ii Child (no progeny)
4 iii Child (no progeny)
+ 5 iv Child
(–''Generation Two''–)
2 Child
6 i Grandchild (no progeny)
7 ii Grandchild (no progeny)
5 Child
+ 8 i Grandchild
(–''Generation Three''–)
8 Grandchild
+ 9 i Great-grandchild
10 ii Great-grandchild (no progeny)
+ 11 iii Great-grandchild
+ 12 iv Great-grandchild
Henry System
The Henry System is a descending system created by Reginald Buchanan Henry for a genealogy of the families of the presidents of the United States that he wrote in 1935. It can be organized either by generation or not. The system begins with 1. The oldest child becomes 11, the next child is 12, and so on. The oldest child of 11 is 111, the next 112, and so on. The system allows one to derive an ancestor's relationship based on their number. For example, 621 is the first child of 62, who is the second child of 6, who is the sixth child of his parents.
In the Henry System, when there are more than nine children, X is used for the 10th child, A is used for the 11th child, B is used for the 12th child, and so on. In the Modified Henry System, when there are more than nine children, numbers greater than nine are placed in parentheses.
Henry Modified Henry
1. Progenitor 1. Progenitor
11. Child 11. Child
111. Grandchild 111. Grandchild
1111. Great-grandchild 1111. Great-grandchild
1112. Great-grandchild 1112. Great-grandchild
112. Grandchild 112. Grandchild
12. Child 12. Child
121. Grandchild 121. Grandchild
1211. Great-grandchild 1211. Great-grandchild
1212. Great-grandchild 1212. Great-grandchild
122. Grandchild 122. Grandchild
1221. Great-grandchild 1221. Great-grandchild
123. Grandchild 123. Grandchild
124. Grandchild 124. Grandchild
125. Grandchild 125. Grandchild
126. Grandchild 126. Grandchild
127. Grandchild 127. Grandchild
128. Grandchild 128. Grandchild
129. Grandchild 129. Grandchild
12X. Grandchild 12(10). Grandchild
d'Aboville System
The d'Aboville System is a descending numbering method developed by Jacques d'Aboville in 1940 that is very similar to the Henry System, widely used in
France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...
. It can be organized either by generation or not. It differs from the Henry System in that periods are used to separate the generations and no changes in numbering are needed for families with more than nine children. For example:
1 Progenitor
1.1 Child
1.1.1 Grandchild
1.1.1.1 Great-grandchild
1.1.1.2 Great-grandchild
1.1.2 Grandchild
1.2 Child
1.2.1 Grandchild
1.2.1.1 Great-grandchild
1.2.1.2 Great-grandchild
1.2.2 Grandchild
1.2.2.1 Great-grandchild
1.2.3 Grandchild
1.2.4 Grandchild
1.2.5 Grandchild
1.2.6 Grandchild
1.2.7 Grandchild
1.2.8 Grandchild
1.2.9 Grandchild
1.2.10 Grandchild
The Huntington Family Association used this numbering system in their family memoir published in 1915, 25 years before Jacques d'Aboville is credited with inventing it. It may very well be true the Huntington family invented this numbering system.
Meurgey de Tupigny System
The Meurgey de Tupigny System is a simple numbering method used for single surname studies and hereditary
nobility
Nobility is a social class found in many societies that have an aristocracy (class), aristocracy. It is normally ranked immediately below Royal family, royalty. Nobility has often been an Estates of the realm, estate of the realm with many e ...
line studies developed by of the National Archives of France, published in 1953.
Each generation is identified by a Roman numeral (I, II, III, ...), and each child and cousin in the same generation carrying the same surname is identified by an Arabic numeral. The numbering system usually appears on or in conjunction with a pedigree chart. Example:
I Progenitor
II-1 Child
III-1 Grandchild
IV-1 Great-grandchild
IV-2 Great-grandchild
III-2 Grandchild
III-3 Grandchild
III-4 Grandchild
II-2 Child
III-5 Grandchild
IV-3 Great-grandchild
IV-4 Great-grandchild
IV-5 Great-grandchild
III-6 Grandchild
de Villiers/Pama System
The de Villiers/Pama System gives letters to generations, and then numbers children in birth order. For example:
a Progenitor
b1 Child
c1 Grandchild
d1 Great-grandchild
d2 Great-grandchild
c2 Grandchild
c3 Grandchild
b2 Child
c1 Grandchild
d1 Great-grandchild
d2 Great-grandchild
d3 Great-grandchild
c2 Grandchild
c3 Grandchild
In this system, b2.c3 is the third child of the second child, and is one of the progenitor's grandchildren.
The de Villiers/Pama system is the standard for genealogical works in
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...
. It was developed in the 19th century by
Christoffel Coetzee de Villiers
Christoffel Coetzee de Villiers (10 March 1850 – 4 September 1887), born in Swellendam as the fourth son of a wagon-maker, and married in Wellington where he then settled, spent his last years as a printer's clerk in Cape Town. His passion for ...
and used in his three volume ''Geslachtregister der Oude Kaapsche Familien'' (''Genealogies of Old Cape Families''). The system was refined by Dr. Cornelis (Cor) Pama, one of the founding members of the
Genealogical Society of South Africa
The Genealogical Society of South Africa is a family history society. The society consists of 11 regional branches as well as an electronic branch accessible online.
The society maintains a large archive of Genealogical material related to South ...
Ancestral File Number
Personal Ancestral File (PAF), as of 2013, is a discontinued free genealogy software provided by FamilySearch, a website operated by the Church of Jesus Christ of Latter-day Saints. It allowed users to enter names, dates, citations and source infor ...
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Ahnentafel
An ''ahnentafel'' (German for "ancestor table"; ) or ''ahnenreihe'' ("ancestor series"; ) is a genealogical numbering system for listing a person's direct ancestors in a fixed sequence of ascent. The subject (or proband) of the ahnentafel is li ...
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Cousin chart
Consanguinity ("blood relation", from Latin '' consanguinitas'') is the characteristic of having a kinship with another person (being descended from a common ancestor).
Many jurisdictions have laws prohibiting people who are related by blood fro ...
(Table of consanguinity)
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Family tree
A family tree, also called a genealogy or a pedigree chart, is a chart representing family relationships in a conventional tree structure. More detailed family trees, used in medicine and social work, are known as genograms.
Representations of ...
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Family tree mapping
Family tree mapping is the process of geocoding places in family tree files to produce geospatial data suitable for viewing with a virtual globe or 2D mapping program.
Overview
The availability of several free applications for viewing geographic d ...
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GEDCOM
GEDCOM ( ), complete name FamilySearch GEDCOM, is a ''de facto'' open file format specification to store genealogical data, and import or export it between compatible genealogy software. GEDCOM is an acronym standing for ''Genealogical Data Commu ...
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Genogram
A genogram (also known as a McGoldrick–Gerson study, a Lapidus schematic or a family diagram) is a pictorial display of a person's family relationships and medical history. It goes beyond a traditional family tree by allowing the user to visual ...
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Kinship terminology
Kinship terminology is the system used in languages to refer to the persons to whom an individual is related through kinship. Different societies classify kinship relations differently and therefore use different systems of kinship terminology ...
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Pedigree chart
A pedigree chart is a diagram that shows the occurrence and appearance of phenotypes of a particular gene or organism and its ancestors from one generation to the next, most commonly humans, show dogs, and race horses.
Definition
The word pedigree ...
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Pedigree collapse
In genealogy, pedigree collapse describes how reproduction between two individuals who share an ancestor causes the number of distinct ancestors in the family tree of their offspring to be smaller than it could otherwise be. Robert C. Gunderson c ...
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Numerical variation in kinship terms
Variations in the number of lexical categories across the languages is a notable idea in cultural anthropology. A former study on "color terms" explores such variations. Brent Berlin and Paul Kay (1969) argued that these qualitative and quantitat ...
Genealogy
Genealogy () is the study of families, family history, and the tracing of their lineages. Genealogists use oral interviews, historical records, genetic analysis, and other records to obtain information about a family and to demonstrate kins ...