There seems to be a blank spot in the history of buff coats. This piece of light armour goes from non extistant to compulsury wear for all and sundry. So out of interest, who can find the earlist reference? I currently have 2 references, one dating from 1601 where an english officer fighting in Ireland manages to scramble free because he's lightly armoured in his buffcoat. There's also this, dated 1605

Hakgobuziers or Dragons
[1605, temp. James I.] Warrant, directed by Sir George Moor of Loseley House co. Surrey to the High Constables of the Hundred of Farnham; Commanding them "to charge all those whose names are here underwritten to provide and showe at Browninges Down on Wensday the twelfth of March next before the Deputy Lieuetenants suche horses " and soe furnished as is hereunder expressed." The underwritten directions, touching the equipment of horses and horsemen, afford the following particulars respecting the earlier dragoons of the seventeenth century, to wit
The armes of a hargohuzier or dragon, which hath succeeded in the place of light horsemen, and are indeed of singular use almost in all actions of Warre; The armes are a good hargobus or dragon fitted with an iron worke, to be carried in a belte, a belte witha flaske, priming box, key and bullett bagg and open heade-peece with a cheeke, a good buffe coate with deepe skirtts, sword, girdle and hangers, a saddle, bridle, bitt, petrell, crooper with strappes for his sacke of necessaries, and a horse of lesse force and lesse price then the cuirassier."
—The warrant is not dated, but the well-known record of Sir George More of Loseley, who was Lieutenant of the Tower temp James L, indicates the period of the writing.

HMC 15th Report Appendix, Part II J.Eliot Hodgkin page 275


Anyone got anything earlier?

David, you seem to be "interested" in buffcoats.