Just finished my second, note-taking pass through the book. Some interesting bits of charr culture in there.
SpoilerCharr matings are not usually for life, though it can happen, and are not necessarily within legion. (For example, Ember Doomforge is Ash Legion and so is her mother, but her grandmother is Almorra Soulkeeper of the Blood Legion.)
It is also mentioned that charr children are placed in the fahrar of one of their parents' legions, which also suggests that cross-legion matings are not uncommon.
Dougal gives a bit of a lecture on the different legions. He states that the Iron Legion attracts warbands with an affinity to explosives and machines, the Blood Legion gathers those that are strong and violent, and the Flame Legion has most of the spellcasters and shamans. The Ash Legion is largely spies and saboteurs.
(The phrasing in that speech -- which is uncorrected by Ember, who was present -- seems to suggest that warbands have a choice in their legion affiliation, and can go where they are attracted. This may or may not apply only to new warbands coming out of the fahrar, but, at some point they have a choice. Could it be that legions have recruiters who visit the various fahrars to try to find likely prospects?)
Warbands are usually 20 members or less, to maintain mobility, though there are exceptions. The warband that the party kills when leaving Ebonhawke seems to have 10 members, based on the kill counts given for each party member. The three warbands that chase them into the Dragonbrand are said to total up to sixty-some charr.
Ember eats some nutbread at one point in the story. Later, when the party encounters some cows, she says that charr are mostly carnivorous. So they are clearly carnivorous, but may not be obligate carnivores, as felines are in the real world.
(Puzzling thing still correlates to the notes on charr culture mentioned above.)
One thing that puzzles me:
SpoilerMention is made of charr farmers, merchants, and other civilians. Where do these come from? They can't all be retired military charr or charr who have lost their warbands. Are there "warbands" that choose civilian pursuits when they leave the fahrar? Or do most civilian charr somehow fail to form groups while in the fahrar, essentially leaving them outside this social-support mechanism that is more important than biological family to other charr? I hope we get some lore eventually that explores these questions.