'ascanian' derives from the name 'Ascania', used in Medieval Latin to refer to the territory and the noble House of Ascania; the English adjective/surname form developed from that place/name.

'Ascania' was used in Medieval Latin and in German as 'Askanien' (German) or 'Askanier' for members of the dynasty; English adopted the adjectival/nominal form 'ascanian' to refer to the dynasty and its members.

Initially the term designated the specific place/name and the noble family ('Ascania' and members of that house); over time it came to be used adjectivally or nominally in English to mean 'relating to' or 'a member of' the House of Ascania.