The Holy Crown of Hungary, also known as the Crown of Saint Stephen, was the coronation crown used by the Kingdom of Hungary for most of its existence; kings have been crowned with it since the twelfth century. The Crown was bound to the Lands of the Hungarian Crown. No king of Hungary was regarded as having been truly legitimate without being crowned with it. In the history of Hungary, more than fifty kings were crowned with it, up to the last, Charles IV, in 1916. The only kings who were not so crowned were Wladyslaw I, John Zápolya, John Sigismund Zápolya and Joseph II.
The enamels on the crown are mainly or entirely Byzantine work, presumed to have been made in Constantinople in the 1070s. The crown was presented by the Byzantine Emperor Michael VII Doukas to King Géza I of Hungary; both are depicted and named in Greek on enamel plaques in the lower crown.
Wikipedia https://en.wikipedia.org/wiki/Holy_Crown_of_Hungary
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