Oh, that's easy.
Reiter is nothing but the german word for rider. Basically any guy on a horse.
And while we are talking about underpowered and settlement battle, what about the moors? Their christian guard are only available in citadels and don't even get an armour upgrade, dismounted polish knights are also available in citadels but have much better armour. and the dismounted polish nobles aren't bad either.dismounted portuguese knights are useless in city battles in comparison to dismounted feudal knights who can take a lot more beating from arrow fire etc. And I don't think aventuros are very useful in city battles.
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