Denier - Burchard III et Otton Ier Brisach

Burchard III of Swabia died in 973 having ruled the duchy for less than two years, succeeding his father Burchard II after a gap during which Swabia was administered directly by the Ottonian crown. The joint attribution to Otto I reflects the political reality of Ottonian-era coinage: ducal issues rarely circulated without implicit imperial sanction, and the mint at Breisach — a strategically critical crossing point on the Rhine — operated under that dual authority throughout this period.

Breisach's position on the river made it one of the more active secondary mints in the duchy, though surviving deniers from this pairing remain scarce.