20 Kreuzers - Adam Frederick of Seinsheim Konventionskreuzer

Adam Friedrich von Seinsheim held the dual role of Prince-Bishop of both Würzburg and Bamberg simultaneously from 1757, an unusual consolidation of ecclesiastical authority in Franconia that gave him outsized political influence within the Holy Roman Empire. His coinage at Würzburg conformed to the Konventionsfuß standard established by the Austro-Bavarian convention of 1753, which pegged the silver thaler at 20 florins and rationalized the fractional denominations accordingly — the 20 Kreuzer being one full-third of a florin under that system.

Production ran across fifteen years, spanning the tail end of the Seven Years' War and into the relative stability that followed, meaning early strikes of this type circulated through a region still absorbing the economic disruption of prolonged conflict in central Europe.