The first Ahnentafel, published by Michaël Eytzinger in Thesaurus principum hac aetate in Europa viventium Cologne: 1590, pp. 146-147, in which Eytzinger first illustrates his new functional theory of numeration of ancestors; this schema showing Henry III of France as n° 1, de cujus, with his ancestors in five generations.
Several genealogical numbering systems have been widely adopted for presenting family trees and pedigree charts in text format. Among the most popular numbering systems are: Ahnentafel (Sosa-Stradonitz Method), and the Register, NGSQ, Henry, d'Aboville, Meurgey de Tupigny, and de Villiers/Pama Systems.
AHNENTAFEL
Also known as the Eytzinger Method, Sosa Method and Sosa-Stradonitz Method, the Ahnentafel allows for the numbering of ancestors beginning with a descendant. This system allows one to derive an ancestor's number without compiling the list and allows one to derive an ancestor's relationship based on their number.
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| The first Ahnentafel, published by Michaël Eytzinger in Thesaurus principum hac aetate in Europa viventium Cologne: 1590, pp. 146-147, in which Eytzinger first illustrates his new functional theory of numeration of ancestors; this schema showing Henry III of France as n° 1, de cujus, with his ancestors in five generations. |
(First Generation)
1 Subject
(Second Generation)
2 Father
3 Mother
(Third Generation)
4 Father's father
5 Father's mother
6 Mother's father
7 Mother's mother
(Fourth Generation)
8 Father's father's father
9 Father's father's mother
10 Father's mother's father
11 Father's mother's mother
12 Mother's father's father
13 Mother's father's mother
14 Mother's mother's father
15 Mother's mother's mother
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.
DESCENDING NUMBERING & REGISTER SYSTEMS
The Register System uses both common numerals (1, 2, 3, 4) and Roman numerals (i, ii, iii, iv). This system is organized by generation, i.e., generations are grouped separately. It was created in 1870 for use in the New England Historic and Genealogical Register published by the New England Historic Genealogical Society based in 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.).
(First Generation)
1 Progenitor
2 i Child
ii Child (no progeny)
iii Child (no progeny)
3 iv Child
(Second Generation)
2 Child
i Grandchild (no progeny)
ii Grandchild (no progeny)
3 Child
4 i Grandchild
(Third Generation)
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 of Arlington, VA) which uses this 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.
(First Generation)
1 Progenitor
+ 2 i Child
3 ii Child (no progeny)
4 iii Child (no progeny)
+ 5 iv Child
(Second Generation)
2 Child
6 i Grandchild (no progeny)
7 ii Grandchild (no progeny)
5 Child
+ 8 i Grandchild
(Third Generation)
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 1.
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. Very similar to the Henry System, widely used in France, 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
MEUGERY DE TUPIGNY SYSTEM
The Meurgey de Tupigny System is a simple numbering method used for single surname studies and hereditary nobility line studies developed by Jacques Meurgey de Tupigny of the National Archives of France, published in 1953.
Each generation is identified by a Roman numeral (I, II, III, etc.), 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,[8] and is one of the progenitor's grandchildren. The de Villiers/Pama system is the standard for genealogical works in South Africa. It was developed in the 19th century by Christoffel Coetzee de Villiers 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.
