Gemeinschaft Interstellarer Soeldner

A type of guild was known in Roman times. Known as collegium, collegia or corpus, these were organised groups of merchants who specialised in a particular craft and whose membership of the group was voluntary. One such example is the corpus naviculariorum, the college of long-distance shippers based at Rome's La Ostia port. The Roman guilds failed to survive the collapse of the Roman Empire.

In medieval cities, craftsmen tended to form associations based on their trades, confraternities of textile workers, masons, carpenters, carvers, glass workers, each of whom controlled secrets of traditionally imparted technology, the "arts" or "mysteries" of their crafts. Usually the founders were free independent master craftsmen who hired apprentices.

Wiki.