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Birkenfeld was a constitutional anomaly — a detached exclave of the Grand Duchy of Oldenburg surrounded entirely by Prussian territory, with no land connection to Oldenburg proper. When the notgeld wave hit in 1921, the district issued its own scrip rather than deferring to any neighboring authority, a small bureaucratic assertion of a jurisdiction that had always been geographically awkward.

Two designers are credited across the series variants: Rud. Wild of Idar and Seche of Köln, suggesting different notes within the 0106 group were commissioned separately rather than conceived as a unified set.