Achaemenid elite units

[MeinPanzer]

If we look at the terracotta figures from the Northern Wei period found in many tombs, we can see a newer form of neck collar used in China. Whole the way around the neck and higher at the back. See photo (with thanks to Duncan Head).
A black/white reconstruction of such a Xianbei figure on which the collar is clearly visible can be seen in A. Dien's book 'Six Dynasties Civilization.
Greetings
Philip

While these figurines (and the panoply of early Chinese cataphracts in general) are much later, this type of collar can be seen in evidence earlier from the first centuries AD in the west (e.g. the Orlat battle plaque) as well as the east (e.g. Dian figural depictions and actual finds).

[etruschi]

Quite right if we date the origin of the Orlat plaque to the 1st century-beginning 2nd century AD as some scholars do. There are however scholars who date the plaque to later Hunnish times (5th century, Hepthalites?). So for the moment nothing is sure.
In the first case we can say the Parthians also used this type of collar, as a black and white reconstruction in Monvert book 'Sassanian armies' suggest.
In the other case the collar was contemporary used in the West as well as in the East (China). In this case the question of who developed it pops up.
Greetings
Philip

[MeinPanzer]

Quite right if we date the origin of the Orlat plaque to the 1st century-beginning 2nd century AD as some scholars do. There are however scholars who date the plaque to later Hunnish times (5th century, Hepthalites?). So for the moment nothing is sure.
In the first case we can say the Parthians also used this type of collar, as a black and white reconstruction in Monvert book 'Sassanian armies' suggest.

The Orlat plaque is one of those items, like the Gundestrup cauldron, that generates a lot of different scholarship. But not all views are equal, and a lot of uninformed scholarship from Pugachenkova onward has skewed the weight of published information out there. Firstly, Nicolle is just plain wrong in identifying the Orlat warriors, or the plaque itself, as Parthian. The region in which it was found was never Parthian, while the burial itself is clearly non-Parthian in nature. Secondly, any date before the late 1st c. BC or after the 2nd c. AD is untenable in the light of current scholarship: see especially J.Ya. Ilyasov and D.V. Rusanov, "A Study on the Bone Plates from Orlat" in Silk Road Art and Archaeology 5 (1997-1998): 107-159 and J.Ya. Ilyasov, "Covered Tail and Flying Tassels" in Iranica Antiqua 38 (2003): 259-325 for two extremely thorough studies of the plaques. There can be no doubt after such studies that they date to between the 1st and the 2nd c. AD, and very likely come from a Kangju grave and depict Kangju warriors (fighting whom is unclear, but what is clear is that they are closely-related nomadic tribesmen).

In the other case the collar was contemporary used in the West as well as in the East (China). In this case the question of who developed it pops up.
Greetings
Philip

The origin can undoubtedly be found in China in the early Warring States period. One must look no further than the burials at Liuchenqiao in the state of Chu and the burial of the Marquis Yi of the state of Zeng, a close neighbour of Chu, both dating from the later 5th c. BC, to see that high collars first originated somewhere in the state of Chu to better protect nobles going to war as charioteers. The collar doesn't appear in the "west" (that is, west of the Tarim basin) until the 4th c. BC, by which time it has been adopted and adapted by the heavy cavalrymen of the Saka.