The following names are taken from the Offizium Rottum of 1424, a collection of Latin documents relating to the area of Xanten, Germany. The edition which I drew the names from presented the data by city. I have not been able to identify all of the cities on modern maps, but those which can be identified are split about equally on either side of the modern day Dutch/German border. The names are recorded in Latin, but show strong vernacular influence, which, in Xanten, was Low German, not High German (and thus the names look more like Dutch than typical German names). Because the names were recorded in Latin, they are sometimes in inflected form; I have converted all inflected forms (which are not otherwise apart of a byname) into their standard nominative forms where no uncertainty is present.
The names show a fabulously delightful assortment of descriptives, usually in terms of relations, some of which are more complex and some less, and the line between byname and simple description is blurred. I have hence had to make a sometimes arbitrary choice concerning when a single name ends. Two patterns leap out for their rarity in other contexts---there are a number of matronymics (a pattern of which I've only seen vague hints of in Dutch before) and scores of "husband of" bynames, which I had never seen before.
The following data are currently available:
The patterns of names used did not differ significantly between men and women, so I have grouped everyone together for the purposes of stastistics. Any type of pattern discussed here would be appropriate for either gender.
35 people were identified simply by a given name with no further description.
30 names followed the pattern <given> + <locative>, where the locative either used Latin de + a Latin generic toponymic element or a vernacular place name, or used a Dutch preposition + a vernacular place name or a generic toponymic element.
20 names followed the pattern <given> + <Latin relational marker> perhaps + <Latin pronoun> or <Latin pronoun> + <Latin relational marker>, e.g., filius eius 'his son', referring to the previously mentioned person. 9 names followed the pattern <given> + <Latin relational marker> without any pronoun. The relational markers and pronouns used are the following:
Relational marker Meaning Number filia 'daughter' 7 filius 'son' 5 frater 'brother' 1 maritus 'husband' 1 natus 'born' (i.e., 'child') 2 soror 'sister' 1 uxor 'wife' 11 Pronoun Meaning Number amborum 'of both' 1 eius 'his/hers' 15 sua 'his/hers' 3
11 names followed the pattern <given> + <byname> where the byname was neither relational nor locative.
3 names followed the pattern <given> + filia/filius + <feminine given name>, with the matronymic appropriately inflected.
2 names followed the pattern <given> + filia/filius + <masculine given name>, with the patronymic appropriately inflected.
2 names followed the pattern <title/descriptive> + <locative>, using the Latin titles domina 'lady' and fratres 'brothers'.
Source: Wilkes, Carl, Quellen zur Rechts- und Wirtschaftsgeschichte des Archidiakonats und Stifts Xanten Band I, (Bonn: Verlag Ludwig Röhrscheid, 1937).