Because there were always some of them in medieval Courts of Europe… Here is another set of Codex Manesse miniatures.
First five minis to the left are monks. Judging by their habits we ave here three monks of the Order of st Benedictus (first, fourth and fifth from the left). Two of them are carrying pastoral staves, are probably abbot and a prior of a convent. With their motto “Ora et labora” Benedictines were one of the oldest and most significant orders in Europe anbd their monasteries were a vital element of medieval landscape (both geographicaly and socialy speaking).
The second and third mini, are monks of Order of st Dominic. Undoubtedly one of the most influential and important orders of late medieval times, with both very bright (hospitals, care over the poor, universities) and dark (involvement in inquisitions and persecution of Cathars, among others) cards in their history. Dominicans (along with Franciscans) being a mendicant and preaching order were perhaps most visible monks in medieval cities, towns and courts.
The next two miniatures despite looking like nuns (of st Benedict perhaps if we assume their dress was supposed to be black), probably are not nuns at all. First because of the hair – nuns wore their hair shorn or cut short while both women sport long braids hidden under their veils, second their cloaks were drawn lined with fur, wich would be quite a luxurious dress for a nun and third because they both held a dog in their hand. A dog of a useless decorative type. It is possible that the dogs carried some significant symbolic meaning I am not aware of bot still I’ve edited the pups out, as IMHO holding dogs in hands look silly. A possible explanation of their looks could be that our ladies are ducal or knightly widows, that moved to a monastery (not necessarily joining a convent) after death of their husbands to live the rest of their life in peace, not to see their sons fighting over their heritage. Or they could be just some young maidens hiding as nuns, or simply wearing extremely dull coloured dress (in comparison to all other ladies in the codex servant maids included). Or medieval female ninja…
The next guy obviously dressed in robe of the Teutonic order, is also probably not a member of the order. The minnesinger known only as Tannhauser (that is “Lord of Tannhausen”) is a quite mysterious figure. Little is known of him except that he was a courtier of Duke Frederick of Austria and Styria, and probably a crusader of the fifth crusade (which would explain the dress, especially if he fought as the guest of the order). To add to the mystery this particular minnesinger is often identified as the lover of Venera from medieval folk tales of late middle ages. (see Tannhauser opera by Wagner based on these tales)
The last gentleman is a Jew. The only one in the Codex. The pointed hat that clearly indicates his ethnicity, was a common (initially) and often compulsory (later) element of jewish dress in medieval Europe. Despite it is now often considered an element of persecution of Jews in europe, initially it was not a derogatory or stigmatizing sign, but one of legal status. In medieval times there was no one law for all. In fact there were many legal systems in force for different groups of people. In many countries (e.g. Hungary or polish principalities and later kingdom) Jews were excluded from jurisdiction of City councils, and subject directly to ducal or royal law and officials similar as knights. (Often these privileges were among the sources of antisemitic resentments in other citizens). Where a knight could be always identified by sword, seals, crest or other attributes, Jews were identified by elements of dress. Initially the pointed hats were worn of their own will and tradition. In time however as Jews adopted the local fashions the distinction were less and less clear, resulting in laws of compulsory dress.