Belemrys,
Both are healess designs. The heal as we know it, did not appear until late in the Medieval period when welted sole shoes appeared.
Having said that, I added a piece of leather where a heal would normally be on the Viking shoes only because I could tell that the edges of the back sole would wear through quickly due to my gimpy leg on one side. I can peal that off and replace it easily and prevent unecessary trips to the shoe repair.