The retinue did not consist of only soldiers…but also of servants, artisans, professionals, estate officials, treasurers, stewards, lawyers and generally all that was needed by the normal operation of society. And, as the lord grew in status, so did the retinue; so that a sort of “bastard feudalism” developed, in which middle ranking figures under a king or major noble would compete for money, offices or influence…. The collective name for these retainers was “affinity,” which also happens to be a word that began in c. 1300 [C.E.] as “relation by marriage.” In a sense, the retinue were “kin,” or part of the “neighbourhood,” words that have developed other meanings over time. For this post, [we will] go on using the word retinue and retainer, but try to keep affinity in mind….
Obviously, this would mean that many persons outside the retinue would always be seeking to be a part of it, if they had no affinity of their own. This meant that outside the retinue were an amorphous group of general supporters and contacts, most of them completely unknown to the lord, but known to the various members of the retinue. Thus, even a minor lord could potentially affect hundreds, even thousands of persons, simply by their existence at the heart of his or her retinue. This made political maneuverings and the raising of an huge army a realistic possibility…. In [Dungeons & Dragons], we tend to think that to raise an army, we need to scatter out agents and interview people. In fact, the more likely truth is that there would be large numbers predisposed to our cause; we would need only to canvas our own connections, gain the support of other nobles and let them canvas their connections, and thus through specific persons already in our employ, we would dredge up the very people we needed from both our lands and from those wanting to be part of our lands. Thus, every war begins with a promise of land—which we will naturally take from the losers, when we win.
All this makes the retainer far, far more valuable than the follower—though, it must be said the retainer has less reason to be directly loyal. Ultimately, the retainer serves the office, not the individual. A lord is sure to be surrounded by trusted, reliable followers and henchmen, the “inner circle,” while sorting out the trusted members of the retinue from those not quite so trusted. In general, the retinue is expected to fall in line because the lord has the retinue’s general welfare at heart; if the lord fights to preserve the lord’s lands, he or she also fights to preserve the retinue’s lands. So all join together in the common cause.
— Retinue vs. Followers – The Tao of D&D
Author’s emphases are in italics. Mine are in bold.