I've now read three James Swallow novels in the Horus Heresy series--The Flight of the Eisenstein, Nemesis, and now Fear to Tread--and this is without a doubt my favorite of the three. I loved The Flight of the Eisenstein and didn't care much for Nemesis, so this was a welcome return to form.
The standout is Sanguinius. Loyalist Warhammer 40k Primarchs are basically Lawful Good Superheroes, i.e. not very subtle. Sanguinius is different because he is sad. If Roboute Guilliman is Superman, Sanguinius is Batman. I appreciated the Gothic, emo atmosphere: Sanguinius being tortured by his legion's secret of the Red Thirst gives the novel a brooding interiority that some Horus Heresy books really do well.
A lot of the supporting characters blurred together for me--they merged into a single composite figure, the good Blood Angel who is fiercely loyal to his Primarch. Meros and Kano were standouts, but they were essentially the same personality. Meros is an Apothecary concerned with keeping things together; Kano, like his Primarch, is burdened by a secret: his prohibited psychic abilities and dark dreams that prophesy doom. Uninteresting, somewhat flat characters, but not unexpectedly so. I know what I'm in for when I read about Space Marines.
What made the novel work was its visual iconography. The bone cathedral, the horrible Ka'Bandha, the disturbing Kyriss, the strange daemons, the cosmic horror dread, the blood-soaked ships: it all landed. If this was a film, I would have been gripped and cramming popcorn into my maw from beginning to end. The whole tableau of daemons fighting Space Marines is so visually and conceptually appropriate: a secular techno-empire doing battle with horrors drawn straight from the human mythological unconscious. This is where Jung becomes useful. I'm sure I've written this elsewhere, but the Chaos Gods are essentially Jungian archetypes: Khorne as the Shadow, the reservoir of rage and violence that civilization suppresses but never destroys; Slaanesh as the unbound Id, the appetites; Tzeentch as the Trickster run amok, the Machiavellian Prince. The Warhammer setting understands, perhaps intuitively, that you don't ever finally defeat these forces, you manage them. Sanguinius's burden with the Red Thirst is exactly this: not conquering the darkness within but keeping it caged. Jung would recognize the situation immediately. The grand irony of the setting is that the Imperium, with its militant rationalism and rejection of the psychic and spiritual, is not the best civilizational structure for actually managing the Shadon. As anyone who has flipped out over somebody eating their hardboiled eggs will tell you (Arrested Development reference), repression never works, it only pressurizes.
I wish I could identify a single major theme, but it's hard with this one; at book 21 of the series, theme is dispersed across the whole Heresy rather than crystallized here, and I think the writers realize this. If anything, this novel is thematically about fighting the rage within, keeping brute strength in check, what we might be inclined to call part of toxic masculinity and/or failure to manage anger. But I don't think Fear to Tread is thematically ambitious so much as aesthetically ambitious. Swallow managed to write a kick-ass Warhammer novel that hit every note. Sometimes that's exactly what you want.
