​​​Genealogy Detective


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Genealogical Numbering Systems
Sharron Mirikitani

Once you have started researching your family for a while, you begin to accumulate mounds of paper and printouts that need organized. You may have acquired original documents and other things that you don't want to get lost in piles of unorganized documents, so what do you do?

One of the best write ups on how to organize your papers is found at http://www.rootsweb.ancestry.com/~sdfpgs/archive/organizefiles.pdf

I, personally have a mixed filing system. My direct ancestors each have a file based on the Ahnentafel or Sosa-Stradonitz System.


Ahnentafel or Sosa-Stradonitz System
This is the most common method of numbering your ancestors. Assign yourself the number 1, then your father is number 2, your mother is number 3, your paternal grandfather is number 4, etc. When using this system, your father's number is always twice your number and his or her mother's number is twice plus one. The Sosa-Strandonitz System, named for the Spanish genealogist Jerome de Sosa, who first used it in 1676. Stephen Kekule von Stradonitz popularized the method in his 1896 Ahnentafel Atlas. Now the system is used worldwide.

(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

The Register System
The Register System is a descendant ordered format, which is accepted by the New England Genealogical Society, one of the oldest genealogical societies in the country This format dates back to 1870 and is used to establish pedigrees.

The Register System uses both common numerals (1, 2, 3, 4) and Roman numerals (i, ii, iii, iv). The system is organized by generation, i.e., generations are grouped separately.

  (–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 Format (Descendant Ordered)
The NGS format dates back to 1912 and is the preferred genealogical report of the National Geographic Society in Arlington, Virginia. It is sometimes called the "Record System" or the "Modified Register System" because it derives from the Register System.

   (–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.[3] 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.[4] 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.[5] For example:

1 Progenitor
  1.1 Child
      1.1.1 Grandchild
      1.1.2 Grandchild
  1.2 Child
      1.2.1 Grandchild
      1.2.2 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

Meurgey 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.[6]

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.[7] 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


Personal Ancestral File (PAF) was 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 information into a database, and sort and search the genealogical data, print forms and charts, and share files with others in GEDCOM format. PAF also linked images and other media files to individual records.

A family tree, or pedigree chart, is a chart representing family relationships in a conventional tree structure. The more detailed family trees used in medicine and social work are known as genograms. Other popular software packages include:


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