"In 1443 what had been but an unimportant mountain fief was erected into a duchy, and the house of Montefeltro ruled a fair territory in the person of the infamous Oddantonio, the first Duke of Urbino. On his violent death in 1444, Federigo, his illegitimate brother, succeeded to the dukedom. Of enlightened mind, as well as of martial capacity, he developed the native capabilities of the country, and gathered about him at the court of Urbino the science and learning of the period. He built a noble castellated palace at Urbino, for the embellishment of which he invited the leading artists of the day. A patron of all art, and a great collector, he encouraged the manufacture of the maiolica wares which flourished under his reign. On his death, in 1482, his son Guidobaldo I. continued his father's patronage to the ceramic artists of the duchy, although much occupied in the Italian wars consequent on the French invasion by Charles VIII. Passeri states that fine maiolica (by which he means that covered with the tin-enamel) was introduced into Pesaro in 1500; and there is some reason to believe that the new process came from Tuscany. It differed materially in composition and manufacture from the 'mezza-maiolica' wares, to which it was very superior, and was known as 'porcellana,' a name applied at that period in Italy to the choicer description of enameled earthen-ware. Passeri also states that in the inventory of the ducal palaces a large quantity of painted 'maiolica' vases were included under this name. The superior whiteness of the enamel, more nearly approaching to that of Oriental porcelain, was probably the reason for its adoption; but we must not confound the term as used in this sense with its technical meaning in reference to a decorative design known as 'a porcellana.'" These famous manufactories of maiolica at Urbino, Gubbio, Pesaro, and Castel-Durante, sprang into life about the end of the fifteenth and the beginning of the sixteenth centuries. That of Urbino perhaps took the lead, being so directly under the patronage of the dukes. The two most distinguished artists here were _Francisco Xanto Avelli da Rovigo_ and _Orazio Fontana_; they are commonly spoken of as "_Xanto_" and "_Fontana_." Besides these were Battista Franco and Raffaelle del Calle, among the best painters upon maiolica.