Some points to aid pondering....
#1 A shield boss means that you have a central grip. The users hand is
in the middle of the shield, the boss protects it. As the user will
naturally 'punch' with the boss, spikes etc were not uncommon.
#2 A horse archer ONLY uses his shield in melee; and only with one
handed melee weapons. So they were not used with bows or lances (used
two handed at this time). If a horse archer carried a shield it had to
be small enough to be slung out of the way. Numerous later examples
suggest that 18"-2ft, 450mm-600mm diamiter was the common size. Despite
official 'equipment lists' including shields, many horse archers don't
seem to use them, they may have been mostly used for dismounted duty,
but with little definate information we do have to speculate.
#3 Most shields (and armour, and weapons) were made in state
'factories' (actually collections of workshops) and issued/sold to the
troops. This was still a period when soldiers spent their own money
adding bling to weapons and armour, additional and non uniform items
appear to have been positivly encouraged. As such, even 'regular' units
could look quite varied.
Tom..
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