1 Groat 'Vierlander' - Philip the Good

The "Vierlander" groat takes its name from the monetary agreement of 1434 binding Brabant, Flanders, Hainaut, and Holland to a common coinage standard — one of the more ambitious currency coordination efforts of the medieval Low Countries. Philip the Good used this arrangement not merely as economic policy but as a tool of consolidation, pressing his scattered Burgundian territories toward practical unity decades before any political union was formalized.

The billon fineness uncertainty — .479 or .399 — reflects genuine ambiguity in surviving assay records, with different mints in the agreement striking to slightly different realized standards despite nominal uniformity.