Katzenellenbogen is a Jewish Ashkenazi surname derived from the name of the former County of Katzenelnbogen, a small medieval state of the German Empire[1] (see also Katzenelnbogen Castle and town).
Protection money paid by Jews was the main source of income for the small principality.
[1] Different spellings of the toponym and surname include Katzenelenbogen and Katznelbogen,[1] with further derivative forms and spellings of the surname like Katsenelenbogen, Catzenellenbogen, Katzin, Katz, Elbogen/Ellenbogen and Bogen.
Katzeneleson, Kazenelson, Kaznelson are further variations of the name[1] by addition of the ending -son, 'son (of)'.