English summary: This present study covers the nicknames of Regensburg citizens that are contained within the Regensburg Sourcebook (c. 893-1378) (Regensberger Urkundenbuch), linguistically rendered and interpreted within their context. Nicknames are characterized as a subgroup of surnames, precursors to our modern family names, in that they should characterize the relevant name-bearer, whether in regard to external traits or to traits associated...