Archbishop Kuno of Trier and his nephew Archbishop Frederick of Cologne had the Weißpfennig minted under the minting union (Münzverein) that they founded on 8 March 1372. The aim of this union was the minting of common gold and silver coins to a fixed fineness. The common gold coin was the gulden, which depicted Saint Peter on the obverse; the common silver coin was the Weißpfennig, which is first mentioned in a document in this treaty. The white appearance that gave the Weißpfennig its name was due to the high fineness attributed to the silver used.
