Maybe it was too obvious, but I'm surprised Burzum wasn't mentioned immediately. Varg is always very open about his beliefs in nationalism/odalism in his blogs and interviews and was involved with the Heathen Front for a time.
2.2 Unpure / Infinitum Obscure / Volahn
2.13 Volahn / The Haunting Presence
4.5 Antaeus / Demoncy / Volahn