Draugar (or the singular form, Draugr) are undead from Norse legend, which form from the corpses of especially malevolent warriors. It was said that, as these warriors died, their will to live proved so strong that their soul could not leave their body, and reanimated it as a Draugr. They retained a semblance of their intelligence, and were tied more or less to the place of their burial, typically a large barrow.
While many modern sources, from D&D bestiaries to MMORPGs have portrayed the Draugr, the original creature of legend was much less well defined- depending on the power of the soul animating the Draugr, it could have different powers and appearances. Some sources even differentiate between standard and aquatic Draugar.
The method of destruction also varied: while some were 'killed' by the same methods as a living man, others could only be destroyed by fire, or by spending the night in its barrow with its severed head on ones knee.
These particular miniatures are from Games Workshop's LotR line, sold as Army of the Dead. I prefer the sculpts as Draugar and thoroughly enjoyed making them look as nasty as possible, adding mold, leather rot, verdigris and rust to the clothes and gear.
This mostly entailed drybrushing in probably 8-10 different shades, along with some overall ink washes. The subtle differences in color make a large difference in the effect, although it can be difficult to tell in pictures.
The sculpts and design are excellent, looking ancient in comparison with a medieval Norse aesthetic. The later medieval 'heater' shields are a slight anachronism, and when I paint more I'll probably replace them with circular shields, but I got these three used, and already assembled.