The earliest spurs were possibly made from wood or bone and probably took the form of "prick" or "prong" spurs, as recorded in Patagonia and Terra del Fuego (de Lacy 1911).
The first recorded metal examples were simple bronze spurs found in Etruscan tombs from the 2nd Century BC, others from that time have been found at Roman sites in Britain. They gradually changed in shape, developing plates that stopped the spike penetrating the horses' sides, or taking on a ball and spike form (as seen in the Bayeux tapestry) that had the same function. Eventually a pyramidal or conical shaped goad developed
Rowels probably originated in France or Spain in the 10th Century A.D., they are first recorded in Britain in Henry III's reign - two seals from 1240 depict the king - on one he wears prick spurs, and on the other rowelled.
In the following centuries spurs became associated with rank and chivalry. We speak of "earning one's spurs" - a disgraced knight would have his spurs and sword broken as part of his punishment.
A knight would wear gold or gilt spurs and an esquire silver .
Through the fifteenth Century rowels became smaller and spur necks became longer. This was so that the spur could reach around the flanchards ( horse armour or barding ) The mediaeval horseman who rode with legs extended forwards also needed spurs with longer necks which could still reach their horse's sides. Over the following centuries, rowels changed shape and size, some developed "jingle-bobs". In seventeenth Century Germany spurs developed multiple necks and rowels, but these were probably for ceremonial or dress use only.
Meanwhile in Spain - spur development was influenced both by Northern European large rowels, and by the large circular heel plate derived from Moorish spurs. The "espuela grande" travelled to America with the conquistadors, this evolved into the various designs of Latin American & Western spur
Latin American spurs include the Mexican or Chihuahua and gaucho spurs categorised as Chilenas, Lloronas and Nazarenas (so named because of the rowel's resemblance to a crown of thorns).
From South America the vaqueros carried spur design north, changing climate and terrain caused regional variations in the shape of Western spurs.
The History of the Spur - Charles de Lacy (The Connoisseur - 1911)
The Loriner - Benjamin Latchford 1883
Eperons - Georges Nabera-Sartoulet
The Country Life Book of Saddlery - edited by Elwyn Hartley Edwards
Tack Explained - Carol Green