You get the majority of your Faction flavor from the Stage 0 Life Modules (which cover Affiliation/Sub-Affiliation). These help guide players in what the core values and traditions of their factions are, including their native languages, and basic skills or traits that define dominant realm-wide cultural values and weaknesses (wealth over honor; survival over status, and so forth). But it's important to remember that, in the end, your character is still an individual, and that the broad-stroke descriptions of the factions are often only skin deep (Draconis Combine is not "space Japan" all the way through, any more than the Lyrans are "space Germany", or the Capellan Confederation is "space China"). This is where you, the player, make the call about what your character considers important.
It was a conscious decision we made to stop micromanaging our players when it came to their role-playing choices.
And, again, the books specifically identified as Era Reports or Era Digests cover just what you're after.
I'd also be remiss if I didn't mention something else: Although the Campaign Tracks featured in various products from the start of the Jihad to present are largely put together with the tactical war game in mind, they make no assumptions about the size and nature of the players' forces, and they very deliberately try to avoid anchoring any such details down. This was done so that clever players and GMs could use those Tracks as fodder for role-playing adventures as well as battlefield events.
A speedy, random example of this (seriously, I just flipped open the book and turned pages until I saw a Track): The Track "Scrap Iron" in Jihad: Final Reckoning, describes an attempt by the fledgling Republic of the Sphere to capture or destroy Precentor Berith, the new leader of the Manei Domini, before he can escape to parts unknown. At face value, the event can be played as a straight battlefield scenario, in which the player's force fields 150% of Berith's force in terms of numbers, with that additional 50% being supplemental spec ops troops of veteran quality sent to help out with the capture--one of whom is the enigmatic agent "Damocles". In the special rules for the Track, both Damocles and Berith are described briefly in terms of skills and capabilities, many of which would have no impact in a Mech battle at all (such as Damocles' +2 Skill modifier on all Action Checks related to Covert Ops and Intelligence on the worlds inside the Republic's nascent boundaries--aka the former Word of Blake Protectorate; as well as a full listing of Berith's implants and prosthetic augmentations). This entire event, although "historically" played out as a Mech battle in a field of rubble-strewn badlands, could be played out instead as a deadly game of cat and mouse by dismounted characters amid the ruins of a war-ravaged town.
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