Every Monday we will post an entry that hasn’t yet been published with a view towards harnessing the collective onomastic power of the internet. If you have any thoughts about the name’s origin, other variants it might be related to, other examples of its use, etc., please share them in the comments! If you wish to browse other Mystery Monday names, there is an index.
Today’s name is an early Germanic feminine name from Austria, with a clearly identifiable deuterotheme: It’s Old High German hiltja ‘battle’. But the prototheme is peculiar, and we don’t recognise it — we would love to see other examples of it, if you have any to share!