Federico da Montefeltro Federico da Montefeltro , also known as Federico III da Montefeltro ( 7 June 1422 – 10 September 1482 ) , was one of the most successful condottieri of the Italian Renaissance , and lord of Urbino from 1444 ( as Duke from 1474 ) until his death . In Urbino he commissioned the construction of a great library , perhaps the largest of Italy after the Vatican , with his own team of scribes in his scriptorium , and assembled around him a large humanistic court in the Ducal Palace of Urbino , designed by Luciano Laurana and Francesco di Giorgio Martini . Biography . Federico was born in Castello di Petroia in Gubbio , the illegitimate son of Guidantonio da Montefeltro , lord of Urbino , Gubbio and Casteldurante , and Duke of Spoleto . Two years later he was legitimized by Pope Martin V , with the consent of Guidantonio ' s wife , Caterina Colonna , who was Martin ' s niece . In the aftermath of the Peace of Ferrara ( see Wars in Lombardy ) in 1433 , he lived in Venice and Mantua as a hostage . In 1437 he was knighted by Emperor Sigismund , and in the same year he married Gentile Brancaleoni in Gubbio . At sixteen he began a career as condottiero under Niccolò Piccinino . In 1441 he distinguished himself in the conquest of the castle of St . Leo , which Federico was to hold for the rest of his life . After Piccinino ' s resignation , he went to Pesaro to defend it against his great enemy in the Marche , Sigismondo Pandolfo Malatesta , lord of Rimini . On 22 July 1444 , his half - brother Oddantonio da Montefeltro , recently created Duke of Urbino by Pope Eugene IV , was assassinated in a conspiracy : Federico , whose probable participation in the plot has never been established , subsequently seized the city of Urbino . However , the financial situation of the small dukedom being in disarray , he continued to wage war as condottiero . His first " condotta " was for Francesco I Sforza , with 300 knights : Federico was also one of the few condottieri of the time to have a reputation for inspiring loyalty among his followers . In the pay of the Sforza — for Federico never fought for free — he transferred Pesaro to their control , and , for 13 , 000 florin s , received Fossombrone as his share , infuriating Sigismondo Pandolfo Malatesta . Despite Federico ' s efforts , the Sforza sovereignty in the Marche was dismantled in the following years . When Sforza left for Lombardy , Sigismondo fomented a riot in Fossombrone , but Federico reconquered it three days later . After six years in the service of the Florence , Federico was hired in 1450 by Sforza , now Duke of Milan . However , he could not perform his duties as he lost his right eye during a tournament . He subsequently carried a vast and disfiguring scar for the rest of his life , so that it was necessary to portray him only on his " good " side . Malatesta profited from his illness to obtain the position under Sforza , whereupon Federico in October 1451 accepted instead a proposal by Alfonso V of Aragon , King of Naples , to fight for him against Florence . After the loss of the eye , Federico – no stranger to conspiracies and one of the leaders that inspired Niccolò Machiavelli to write " Il Principe " – had surgeons remove the bridge of his nose ( which had been injured in the incident ) . This improved his field of vision to a considerable extent , rendered him less vulnerable to assassination attempts – and , as can be seen by his successful career thereafter , restored his merits as a field commander . In 1453 the Neapolitan army was struck by malaria , and Federico himself risked losing his healthy eye . The Peace of Lodi of the following year seemed to deprive him of occasions to exhibit his ability as a military commander . In 1458 the death of both Alfonso and of his beloved illegitimate son , Buonconte , did not help to raise Federico ' s mood . His fortunes recovered when Pius II , a man of culture like him , became Pope and made him Gonfaloniere of the Holy Roman Church . After some notable exploits in the Kingdom of Naples , he fought in the Marche against Malatesta , soundly defeating him at the Cesano river near Senigallia ( 1462 ) . The following year he captured Fano and Senigallia , taking Sigismondo Pandolfo prisoner . The Pope made him vicar of the conquered territories . In 1464 the new Pope Paul II called him to push back the Anguillara , from whom he regained much of the northern Lazio for Papal control . The following year he captured Cesena and Bertinoro in Romagna . In 1466 Francesco Sforza died , and Federico assisted his young son Galeazzo Sforza in the government of Milan , and also commanded the campaign against Bartolomeo Colleoni . In 1467 he took part in the Battle of Molinella . In 1469 , on the death of Sigismondo Pandolfo , Paul sent him to occupy Rimini : however , fearing that an excessive Papal power in the area could also menace his home base of Urbino , once having entered Rimini Federico kept it for himself . After defeating the Papal forces in a great battle on 30 August 1469 , he ceded it to Sigismondo ' s son , Roberto Malatesta . The matter was solved by the election of Pope Sixtus IV , who married his favorite nephew Giovanni Della Rovere to Federico ' s daughter Giovanna , and gave him the title of Duke of Urbino in 1474 ; Malatesta married his other daughter Elisabetta . Now Federico fought against his former patrons the Florentines , caught in the Pope ' s attempt to carve out a state for his nephew Girolamo Riario . In 1478 Federico was involved in the Pazzi conspiracy , However , after the death of his second wife Battista Sforza ( daughter of Alessandro Sforza ) he spent much of his time in the magnificent palace in Urbino . In 1482 he was called to command the army of Ercole I of Ferrara in his war against Venice , but was struck by fever and died in Ferrara in September . Federico ' s son , Guidobaldo , was married to Elisabetta Gonzaga , the brilliant and educated daughter of Federico I Gonzaga , lord of Mantua . With Guidobaldo ' s death in 1508 , the duchy of Urbino passed through Giovanna to the papal family of Della Rovere — nephews of Guidobaldo . The Renaissance Man . Federico , nicknamed " the Light of Italy " , is a landmark figure in the history of the Italian Renaissance for his contributions to enlightened culture . He imposed justice and stability on his tiny state through the principles of his humanist education ; he engaged the best copyists and editors in his private scriptorium to produce the most comprehensive library outside of the Vatican ; he supported the development of fine artists , including the early training of the young painter Raphael . He patronised the writer Cristoforo Landino . Federico commissioned for himself a " studiolo " ( a small study or cabinet for contemplation ) in both his palace at Urbino and that at Gubbio ; both are celebrated for their " trompe l ' oeil " decoration executed in marquetry . The former is still in situ , the latter was eventually purchased by and brought in its entirety to The Metropolitan Museum of Art . . Federico took care of soldiers who might be killed or wounded , providing , for example , dowries for their daughters . He often strolled the streets of Urbino unarmed and unattended , inquiring in shops and businesses as to the well - being of the citizens . All citizens , regardless of rank , were equal under the law . His academic interests were the classics , particularly history and philosophy . All his personal and professional achievements were financed through mercenary warfare . Through dedication to the well - being of his soldiers , his men were enormously loyal and , incredibly , he never lost a war . He was decorated with almost every military honor . Edward IV of England made him a Knight of the Most Noble Order of the Garter ; he wears the Garter bound round his left knee in the portrait by Pedro Berruguete .