Wonderful Duncan, I was able to find it on the shelves,. I knew I had read something about them years ago and couldn't put my finger on where.
Bachrach's conclusions are that:
Franks = Franks
Burgunfians = Burgundians from Savoy
Saxons= Roman military colonists (federates) from around Bayeux
Sarmatians gentiles settled in military colonies around Gaul in the IVth century as we said
Litacani are Laeti as said and both they and the Sarmatians appear in the Notitia which Bachrach dates to 408
Ripari have been taken as Ripuarian Franks, but this is a designation from the VIIIth century.
Olibriones should be Roman soldiers , but they are not mentioned in the Notitia.
Bachrach suggests that Riparii are Riparienses . Riparii is a term that is used to designate Egyptian poilice officers so they could be Roman soldiers whose role has declined to paramilitaries.
B thinks that there may be a confusion within the text and that Olibriones should really be read as (O) a redundant O, (liberi) meaning free men and (ones) which is there to mirror Burgundiones and Saxones as Jordanes mirrors Armoricani with Litacani, the Liti or Laeti.
Thus there are no Olibriones, they are conjured from an adjective that describes Riparienses, Roman soldiers who now look like Llaeti, but are free and thus legally distinguished from them.
Roy