So you posit just the usual process of forgetting more remote blood relatives that are no longer of importance. I agree.
Makes sense to me. This would allow to check many Gifted children found by traveling Redcaps for consanguinity with Mercere, wouldn't it? And these children would then be claimed preferentially by House Mercere, right? So we have the current Magical Merceres drawn from a significantly larger reservoir than just the few 1000 or so descendants of Mercere the House can remember and track.
If the overall size of this reservoir reaches some 30000 (still far less than the million or so theoretically available), the number of Gifted persons found within it and claimed by the House over a century - some 10 - would roughly fit the numbers calculated by Mark Shirley in sub rosa #14 p.28 Supply of Apprentices and Prevalence of The Gift as the absolute minimum for the Order to exist as it is in 1220: one Gifted birth per 49,000 people in every seven years.
So in that case the descendents of Mercere would not have a significantly higher percentage of Gifted people than the general population of Mythic Europe.
It might be, that some Magical Mercere just desire to teach the apprentice they themselves have chosen, instead of waiting for a thin-blooded Mercere scion assigned to them by the House.
There were some very old house rules once posted the old Durenmar.de website:
Roll a stress die vs 21
add 3 once per parent for any magical/faerie virtue
add 6 per parent gifted (this supercedes the above)
add the Magical Aura or Half the Faerie Aura (round up or down, pick one)
So, two magi in an aura of 3, roll a stress die +6+6+3 vs 21.
two parents who have a several magical virtues without the gift in a divine aura of 1 roll a stress die +3+3 vs 21.
I found in my sagas that I increased it to 24, and specified that these rules were explicitly made for the players, and did not govern how easily other people had magical children.
I think Mercere would care about legitimacy not because the descent from Mercere is in question (as you say, trivial to determine this via InCo), but because of concerns about the possible polluting effect of the other blood.
What if they get faerie blood in the bloodline? Or Tremere blood or whatever? What if a Gifted Mercere descendant has more faerie blood than Mercere blood? Is their Gift truly inherited from Mercere?
Also House Mercere might believe (rightly or wrongly) that if the quotient of blood in an individual that is true Mercere blood falls too low, then the chances of breeding further Gifted individuals in that line is lessened.
The order size is definitively underestimated. HoH gives 1240 magi in the order, but it must be taken into account that their life expentancy is a lot higher than usual, over 3 times longer than average (so magi may be born as statistics, but as they actually last longer their percentage over total population must be higher). But you also have to take note of every one gifted people out there, from sorcerers to the unlucky ones who got the Gift to receive in return just the social penalties of it from their fellows.
I just read articles about the early dead of children during the middle-age where it was stated that around half of the children not reach adulthood. It was also mentioned that children especial problematic one get regular birching.
Maybe for gifted the chance to survive increase by a lot when they are kidnapped early by a faerie compared to when they stay at the home of a normal family especial when the family live in a city.
The population of Europe is approximately 70 million in 1225. The population of the nobility is approximately 10% of that. If the population of the Gifted were 1/1000th of the nobility alone, it would be about 7,000; of them, only about a fifth are in the Order.
I find that unlikely, but do not have a better model at hand.
Of course, the Gifted are not especially self-sustaining. Aside from how inheritable the Gift is, magi are somewhat self-destructive. They have relatively few apprentices, partly from disinterest (I suspect) and partly because they don't live very long. The average age of example magi is less than 50, if I recall correctly.
Note, that the definition of nobility varies considerably with time, culture and country.
But 10% is an upper limit rarely reached: maybe in countries where entire strata of land owners and warriors became nobles, like the Castilian Hidalguía or the Polish Szlachta.
Perhaps TimOB explains us, of which time and country he is thinking?
Don't forget useless hangers on and third sons of third sons...
noble children were more likely to make it to adulthood, and less likely to be able to take up the family business as it were. A lot got sent into the priesthood, which as a result (along with other factors) became highly political at the time... better roads and communications as time went on meant more consolidation of power and thereby fewer positions for a growing aristocracy...
in somewhere like Germany or Italy where local nobles retained a certain degree of independence it could have gotten towards 1%, but 10% would be silly- 9 peasants per noble?
For what it is worth, I think that either 10% is way too large, or a very broad definition of "nobility" is being used.
When researching The Church the best numbers that I could find for clergy in 1220 was about 2% of the population. Remember that this includes monks, parish priests and clerks etc.
I think that at best the percentage of nobility would be similar to that of the clergy (i.e. around 2%).
I have seen some numbers of up to 10% nobles quoted for parts of medieval Europe. However, as I understand it, those numbers include very, very minor individuals. Essentially only peasants who have a fancy name, and supposedly an illustrious ancestor, but have no more influence, power, or resources than any other peasant. So not nobles in any functional sense. It's kind of like someone today who has "von" in their name claiming to be a noble. Technically, it is true that "von" may indicate an ancestor who was at least a minor noble, but that doesn't make their modern descendants aristocrats.
an accurate percentage will vary by date, location, and the definition of nobility.
pasting from Wikipedia:
The countries with the highest proportion of nobles were Castile (probably 10%), Polish–Lithuanian Commonwealth (15% of an 18th-century population of 800,000), Spain (722,000 in 1768 which was 7–8% of the entire population) and other countries with lower percentages, such as Russia in 1760 with 500,000–600,000 nobles (2–3% of the entire population), and pre-revolutionary France where there were no more than 300,000 prior to 1789, which was 1% of the population (although some scholars believe this figure is an overestimate). In 1718 Sweden had between 10,000 and 15,000 nobles, which was 0.5% of the population. In Germany 0.01%.
Apparently in Castile if you owned property and were head of household, you qualified as a noble...
Indeed. Castile and Poland-Lithuania had extremely broad definitions of nobility - in Poland, a significant portion of the nobility was in fact Jewish, while in Castile nobility was literally a matter of owning horse and arms. In lands where the definition and privileges of nobility are more restrictive, you get a smaller noble class.
Yes. So the definition of "noble" in this case only really means "not a serf (nor clergy)". It's what "freeman" means in other parts of Europe. It's effectively conflating the aristocracy and the middle-class.
Also 18th century demographics are possibly not too relevant to 13th century ones.
record keeping in the 12th and 13th centuries being what it was, those numbers are the ones that are available, and at least give a concept of the range of answers...
This is the one part of this thread I can help with. I’m the one who assembled the expanded Magi of Hermes chart. The average age of an NPC magus with a complete stat block across all ArM5 is 60.
But that’s not their age at death! And it would be a mistake to think the average magus dies at 60.
That would be a mistake. It just indicates a relatively young population compared to their potential age. Considering there are outlier magi of around 180 years, it seems magi tend to be youngish. I haven't done a chart to analyze it, although that might be mildly interesting.
In sub rosa #14 (February 2014) p.24 Current Size and Age Profile, especially box Age Distribution of the Order, Mark Shirley provides an age distribution of all the 261 magi from the Tribunal books then available (that is, with only F&F missed):
Spring (Gauntlet – 35 years out of Gauntlet) 14.20%
Summer (36 – 70 years out of Gauntlet) 42.50%
Autumn (71 – 120 years out of Gauntlet) 34.10%
Winter (121 – 180 years out of Gauntlet) 8.80%
Deep Winter (181+ years out of Gauntlet) 0.40%He writes: "What is immediately noticeable is that the Order of Hermes is dominated by Summer magi, with Autumn magi being the second most numerous."
Indeed, this is not a typical age pyramid of medieval populations at all: it is top-heavy and bound for a serious drop in numbers in the next decades.
As PC magi are usually Spring magi, to get closer to actual sagas Mark Shirley also provides a second distribution with 5 extra Spring magi added per Tribunal:
Spring (Gauntlet – 35 years out of Gauntlet) 23.00%
Summer (36 – 70 years out of Gauntlet) 38.10%
Autumn (71 – 120 years out of Gauntlet) 30.60%
Winter (121 – 180 years out of Gauntlet) 7.90%
Deep Winter (181+ years out of Gauntlet) 0.30%
This is still an age pyramid unsustainable over the years.
I reckon that it would cause the Primi no small headaches: perhaps Andru's instigation of a new wave of apprentices for House Jerbiton (the antigones from HoH:S p.43) will be emulated by other Houses soon.
So it appears that lots of magi wanna find Gifted children!
I don't have this sub rosa at hand but if they only used the magus that have stats given then there is a big problem as i.e. Fangheld have 7 magus with stats but there are 5 more not worked out in the main house not to mention the many chapter house they have. Also many or even most of the "Spring age" magus from the Rhine Tribunal are current wandering from Covenant to covenant and have no info given at all.