Frederick III, called the Simple, was King of Sicily from 1355 to 1377. He was the second son of Peter II of Sicily and Elisabeth of Carinthia. He succeeded his brother Louis. The documents of his era call him the "infante Frederick, ruler of the kingdom of Sicily", without any regnal number.
Frederick III was born on 1st September 1341 in Catania. In his youth, the reign was under the control of powerful Sicilian barons, in particular of Artale I Alagona. The beginning of Frederick III's reign was also plagued by intermittent wars with the Kingdom of Naples and also by the Black Death, to which his elder brother and predecessor had succumbed.
On 25 December 1369, Frederick ordered all Jews to wear a badge indicating their heritage. The badge consisted of a piece of red material, not smaller than the largest royal seal; men were required to wear it under the chin, and women on the chest. In 1372 he was able to come to peace terms with Naples and Pope Gregory XI, obtaining the title of tributary King of "Trinacria".
Depicted here is a Pierreale issued under his reign. The obverse of a coin illustrates the Crowned eagle standing left, his head turned to the right, with his wings displayed; all within October, annulet in each external void. The reverse of a coin represents crowned coat-of-arms.
Image Source: Wikepdia.org