Denier - Béla IV Klippe

Béla IV's reign was defined almost entirely by the Mongol invasion of 1241–42, which devastated Hungary so thoroughly that contemporaries estimated half the kingdom's population perished. The irregular klippe format of this denier — a square-cut flan rather than a round one — almost certainly reflects disrupted mint infrastructure in the invasion's aftermath, when maintaining consistent round blanks was not always possible.

Béla spent his later decades rebuilding the kingdom, fortifying towns and reorganizing the coinage. Square-cut pieces from this reign turn up in hoards buried during the invasion years and never recovered.