Sunday, April 26, 2020

Saturday Night Genealogy Fun: What Is Your Birth Surname Henry Number?

Tonight for Saturday Night Genealogy Fun Randy Seaver has us poking around in our genealogy databases.

Your mission, should you decide to accept it (cue the Mission:  Impossible! music here), is:

(1) Do you know what a "Henry Number" is?  It is a descendant numbering system from a specific person.  The Wikipedia article for Genealogical Numbering Systems describes it as:

"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."

(2) Go to your earliest known ancestor with your birth surname in your software program and calculate your Henry Number from that person.  Show each generation of your line of ancestors with your birth surname with their Henry Numbers.

(3) How did you calculate the Henry Numbers?  What do these numbers tell you?

(4) Tell us in your own blog post, in a comment on this blog post, or in a Facebook post.

2.  Well, my birth surname is the same one I have now, Sellers.  When I checked my database, I discovered that I have 575 Sellerses in there.  Going back in time from myself, the earliest ancestor I have with the name Sellers is only seven generations back, because before him the name was Söller (of which I have four generations in the database).  Here's my Sellers line:

1 John Sellers (1731–1783)
11 Abraham Sellers (1758–1831)
11X Peter Franklin Sellers (1800–1863)
11X1 Cornelius Godschalk Sellers (1845–1877)
11X12 Cornelius Elmer Sellers (1874–1918)
11X121 Bertram Lynn Sellers (1903–1985)
11X1214 Bertram Lynn Sellers, Jr. (1935–2019)
11X12142 Janice Marie Sellers (1962–living)

3.  I calculated the Henry Numbers manually.  I started with the first generation with the name Sellers and moved forward through time.  Not only is creating reports in Reunion something I don't enjoy, it didn't give me an option of using the Henry Number system.

Two things I had to contend with which are not described in the handy-dandy description that Randy quoted are an adoption and multiple marriages.  My grandfather was informally adopted by Elmer Sellers and was not his biological son.  Since Elmer was the only father my grandfather knew, however, and since neither my grandfather nor any of his siblings knew this was the case, I counted my grandfather as child #1.

My father was the first (and only) child of my grandparents, but he was my grandfather's fourth child, because my grandfather had three children with his first wife.  Since this system follows the father, I counted my father was child #4.

I was the first child of my parents, but my father and his first wife had a child before me.  Again, following the father, I am child #2.

4.  I have this blog post, a comment on Randy's blog, and a Facebook post!


  1. I am impressed that you calculated all this out by hand. It is a very cumbersome system to use without software.

    1. Maybe it's because I'm a numbers geek, but I did not find it cumbersome. I found the numbers easier to deal, and easier to understand, with than the Ahnentafel system.

  2. Wow, your process was more complicated and a lot of thinking you had to do.

    1. The description of the Henry system doesn't mention adoptions or multiple marriages, but the logical extension wasn't too difficult, at least as I understood it. I don't know if Mr. Henry would approve!


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