SAAR

The Saar Protectorate was a country / city state that was administered by France between the two world wars (1920 -35) and again after after the second world war from 1947-56, after which it reverted back into Germany. The Saar Franc was used alongside French francs and there was a short lived trial of using Saar Marks.

This is the half franc or 50 Centime note from 1930 . the portrait is difficult to see and the note (or country ) is not listed , so I'm making an educated guess at the portrait being Mercury - although it looks vaguely female!! French notes used mercury at this time