Yes, although lackey probably suggests a slightly negative connotation. Many medieval and early modern European societies had what we call a patron-client relationship. (The musketeers are set in 17th c. France). I am most familiar with the Iberian manifestaion of this social relationship. Wealthier men (patrons) demonstrated their wealth and status by maintaining large households. Often this could include retainers, lackeys as you call them. In Spanish we would call them criados. This can be a tricky word as in some cases it could refer to paid help while in others it refered to unpaid, but financially supported retainers.

Frequently, criados were young men from related families or families tied to the patron. These could parallel marriages. The younger brother of a bride could be sent to live as a criado with his brother in law. Or a nephew might be sent to live with a uncle. In some cases, criados were expected to learn skills, though not necessarily as tradesmen or artisans who would learn through the guild system. Instead a criado might be expected to learn something about a particular kind of business or mercantile endeavor. Sometimes criados could serve as "muscle" but they could equally serve as pages, or personal attendants, or scribes.

Women could become members of households too as criadas. Similarly to men they would be closely tied to the matriarch of the family. Like men they usually had some familial or social tie that led to their incorporation in the household. They too could be expected to learn the affairs of the house and oversee paid help. Often the patron was expected to help find a suitable spouse for his female wards.

In large households affairs between criados and criadas were not uncommon. Criadas could also find themselves victims of sexual violence from patrons or criados. Such situations were serious because part of the position of patron included protecting the chastity of criadas and maintaing an honorable, pious home. Sexual liasons outside marriage, between unmarried members of the household, were dishonorable and brought stain on the honor of the patron.

These sets of relationships were vital in the period of Spanish expansion into the Americas. Many conquistador companies formed as criados followed patrons. For example, Hernan Cortes was a criado to Diego Velasquez, governor of Cuba, before setting off on his own, and disobeying his former patron. The most successful conquistadors quickly set up large households and began to exchange criados and criadas with each other as they established new social circles in the Americas.