So a while ago now, I made a little table trying to calculate CS and US casualties in the Second Great War by comparing them to German and Russian/Soviet casualties in both wars in OTL. The experiment produced what I thought were some pretty interesting numbers, but I've come up with a new idea for looking at how we might compare GWI and GWII casualties; the ratio of civilian to military PoVs in Breakthroughs and In At The Death, at the height of both wars.
Firstly looking at Breakthroughs;
Reggie Bartlett · Combatant
Flora Blackford · Civilian (Historical Figure)
Sam Carsten · Combatant
Anne Colleton · Unclear
Abner Dowling · Combatant
Cincinnatus Driver · Field Personnel
George Enos · Combatant
Sylvia Enos · Civilian
Jake Featherston · Combatant
Lucien Galtier · Civilian
Roger Kimball · Combatant
Chester Martin · Combatant
Arthur McGregor · Unclear
Gordon McSweeney · Combatant
Irving Morrell · Combatant
Jonathan Moss · Combatant
Jefferson Pinkard · Combatant
Scipio · Unclear
Nellie Semphroch · Unclear
We see we have 11 direct combatants, 2 "home front" civilians, 1 civilian who already qualifies as a historical figure by the start of the book (Flora), 1 serving non-combatant (Cincinnatus), and 4 people who are technically civilians but for one reason or another (spying, partisan warfare, anti-partisan warfare) I choose to classify ambiguously.
Now lets compare to In At The Death;
Flora Blackford · Civilian (Historical Figure)
Sam Carsten · Combattent
Jerry Dover · Combattent
Abner Dowling · Combattent (Historical Figure)
Cincinnatus Driver · Field Personnel
George Enos Jr. · Combattent
Jake Featherston · Civilian (Historical Figure)
Armstrong Grimes · Combattent
Cassius Madison · Combattent
Chester Martin · Combattent
Irving Morrell · Combattent (Historical Figure)
Jonathan Moss · Combattent
Leonard O'Doull · Field Personnel
Jefferson Pinkard · Unclear (Historical Figure)
Michael Pound · Combattent
Clarence Potter · Unclear (Historical Figure)
Jorge Rodriguez · Combattent
Here we have 9 direct combatants, no-one on the home front, 2 officers of historical significance (Morrell and Dowling), 2 leading politicians (Flora and Featherston), 2 non-combatant field personnel (Cincinnatus, O'Doull), and 2 members of the confederate military with ambiguous combat roles, both of whom are historical figures (Pinkard and Potter). Note that while Cassius Madison is certainly a historical figure by the end of the book, I choose not to list him as such because he's not of great importance at the start of the book.
What interests me most about these numbers is the complete lack of "average people" on the home front of GWII, and the extreme influence in importance of the remaining characters from the Great War Trilogy.
Lets play some games with these numbers; lets suppose the fraction of combatant PoVs in both books represents an arbitrary "mobilisation level". Full combatants have a value of 1/the total number of PoVs, while unclears and non-combatants count for 0.5, while full civilians count for 0. With these values we get these numbers:
Breakthroughs/GWI: 13.5/19 (0.71)
In At The Death/GWII: 13/17 (0.76)
Pretty similar at first glance right? Now lets see what happens when we remove all historical figures:
Breakthroughs/GWI: 12.5/18 (0.69)
In At The Death/GWII: 10/11 (0.91)
It might seem a bit arbitrary, but Morrell and Featherston's experiences aren't really representative of most people in the war, and counting this way essentially makes it a ratio of how many average people Turtledove presents are involved in the war, which is best for what we're about to do next.
This is the ratio between the "mobilisation levels" of each of the books:
(10/11)/(12.5/18) = 1.31
Multiplying each country's GWI casualties by this number gets us:
USA: 1.1 Million*1.31 = 1,440,000
CSA: 0.9 Million*1.31 = 1,178,182
These numbers aren't perfect; the method to achieve them is admittedly very arbitrary, and they seem a bit low for my liking, but I think they are interesting, and the premise of looking at the proportion of characters directly involved in the war effort is probably the best evidence we can hope to glean from the text.