1. The guardsmen were first and foremost Mercenaries, but did they have an official selection process? Or was admission solely reliant upon reputation?
2. Did they have a formalized training process where they were accustomed to Byzantine military formations/tactics? Which leads me to my next question...
3. How much of an impact did retired guardsmen have on Norse warfare when they returned home? That is to say, did they introduce Eastern/Byzantine military tactics/armor/weapons to other Scandinavians?
4. What would most Guardsmen do following retirement? Were there Scandinavians who chose to remain in Constantinople? Was it common to see Guardsmen go on to serve as housecarls (obviously after retiring)?
5. I have read that the Guard was respected by Scandinavians, is that true? How did native Byzantine's feel about the guard?
6. Initially, the majority of the guardsmen were Swedes but eventually Norse, Danes and Icelanders became the majority - why did this happen? And prior to the conquest of 1066, how common was it to see Saxons serving in the Guard? And were Frisians known to serve as well? And is it true Irishmen and Scots even served?
7. Compared to the average Housecarl, how much training did a guardsmen receive?
8. Were most guardsmen Pagan, or did most convert to Christianity?
9. Childish question, but how do any of the sources discuss Harald Hardrada's fighting capability?

And if you guys could recommend any books on the Guard and Harald Hardrada in particular, I would really appreciate it.

Thanks