Timeline from the fifth century. B.C. at the end of the second century. A.D. (Septimius Severus imp.)

A - SHIELDS CIRCULAR

  A1 - Shield hoplite
   - Domed without umbone
   - Typically scaled with Gorgon's head
   - Diameter of 90 cm
   - Fully decorated in the imperial period
  A2 - Shield Macedonian
   - Domed without umbone
   - Astral motifs, arches on the margins, inside with arches, stars or rosettes
   - Initial shape of the arches similar to horseshoe (IV BC), in more open below, double or triple (III BC) finally circular arcs (II BC et seq)
   - Internally bosses, growing in size and more refined over the centuries
  A3 - Circular shield with thorn (Parmae?)
   - Allied with B1a (without oval)
   - Western
   - Quartered with crosslinked or headbands (Celtic)
   - Used by the Roman cavalry during the Macedonian wars, replaced by A4
   - From the late Republican period and the beginning era Augustea
  A4 - Shield with mixtilinear profile and umbone (Parma)
   - Profile "S"
   - Late Republic First Empire
   - Little decoration, 4 leaves or radially undulating and human head on umbone (parma equestris)
   - From the seventh century BC to the first/second century AD
  A5 - Circular shield plate with umbone circular boss
   - Last long
   - Shortly decorated, reinforcements radially and / or grating or studs covering all
   - European peoples (maze -> Iberian) (studs -> Celts)
  A6 - Shield mixtilinear with central decoration
   - Similar to A1, the central part in recess with figurative emblem (Imperial Age)
   - Gorgonia, protomes animals and heads of gods
   - Barbarian peoples
  A7 - Circular Shield curved free margin (edge)
   - Two dogs or wolves, not in the center but on one side (the tomb of Pergamon)
   - Maybe Eastern peoples
  A8 - Circular domed shield with ribbed surface
   - Umbone hinted
   - barbarians
  A9 - Buckler
   - No decorations, powerfully domed, no edge
   - Greece, knights
   - Gladiators

                                 Decorations of "A" Shields

1 Head of Ammon - A8 (Africa?)
2 Bust Artenis Tauropolos - A1 (Numidian monuments, Macedonian coins, perseo)
3 Diòscuro on horseback - A1 (late Republican, ordo equester ?, Rome)
4 of Perseus Bust - A1 A2 (Numidian monuments, Delo, Macedonian coins)
5 Bust Romae-Virtus - A1 (tardorepubblicano, Rome)
6 Aquila and epigraphic chart - A1 (tardorepubblicano, Rome)
7 Thunderbolt winged - A1 (symbol of Jupiter)
8 Gorgoneion - A1 A6 A8
9 Gorgoneion with Aegis or scaly surface - A1 (Aegis = crown of clouds)
10 Clava of Hercules - A1 A2 (Numidian monuments)
11 Dog or Wolf - A1 A6 A7
12 Lion rampant A1
13 lion ravening bull A1
14 Protome Leo A1 A6 (also with launches in its jaws, Alessandro seal?)
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B - SHIELD LENGTHENED

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