I’ve finally gotten around to reading Robert Bartlett’s The Making of Europe: Conquest, Colonization and Cultural Change, 950-1350, which I bought two decades ago, and have just run across an interesting passage on the history of the miles (horseman/knight):
Heavy cavalry retained its importance throughout the period discussed here, 950-1350. Not all such horsemen were knights. Indeed, one of the most important aspects of the history of the period is the very complex interplay between the purely military and the social meanings of the word ‘knight’ — cavalier and chevalier, Reiter and Ritter. The Latin miles did service for both, and the semantics of this term have been investigated minutely by historians. A man described as a miles in the early eleventh century was usually simply a heavy cavalryman, a loricatus; there was normally no implication of high social status — in fact, sometimes the opposite, for at this time the milites were contrasted with the magnates or great nobles. For example, when William the Conqueror deigned to consult his men on the question of his assumption of the crown in 1066, the viscount of Thouars, a man of ancient lineage, commented: ‘Never or hardly ever have milites been summoned to such a decision!’ The milites were a rough and ready crowd, vital but hardly to be idolized. Already, however, in the eleventh century, in some places, the term had begun to acquire an honorific meaning, a development which was to strengthen and spread over the following centuries. In the eleventh century it was possible to make a man a miles by giving him a horse and armour; by the thirteenth century the knight was a member of a closed, hereditary class. Social exclusiveness, religion and romance combined to reshape the meaning of the word.
This historical reenactment may illustrate some of the finer points. (NSWF: language, violence.)