GradiusCaelius
Regular
Good thing there are alot of sources for dark age britian out there. If you combine that with dark age Eastern Rome sources then you I think you could accuratly represent Europe in that time frame. Not sure if you have any of the Total war games but the Medieval II mod Invisio Bararorum has a sub mod set in britian/northern france area that I felt accuratly represented things. You could use that as a reference if you think it would help with the armor and weapon designs. Not sure if the people of good old Hybernia acted as mercenaries at that time but if you find info on that then Gaelic mercenaries could be a neat addition.