It's not just the northerner infantry, it's everything. That one hero character is the spitting image of James Cosmo as Jeor Mormont of the Night's Watch. Those as of yet unfunded soldiers of the other human faction look almost identical to Lannister troops as shown on GoT, a style I don't believe ever existed historically, even if it is a combination of a variety of historical styles from around the world. The middle guy too is the spitting image of Charles Dance as Tywin Lannister.
If I were to abandon sense and give in to my creative inspiration to make the army of Gilles de Raux, those zombified northerner soldiers would fit in well. That armour could, based on painting, either pass off as leather or padded armour. Those zombified lannisters though, they'd stick out, and only being two poses, it wouldn't help to separate them alone into something else, like Grave Guard.