He was born as Ioan Micu in Sadu, nowadays in Sibiu County, in 1692 from a lower-class family. He studied by the Jesuits in Cluj and trained in theology in Trnava. On 18 November 1728, following the death of previous bishop Ioan Giurgiu Patachi, the electoral synod convened and Micu resulted the more voted, even if he was young and he had not yet terminated his studies. Accordingly, on 12 July 1729 the Habsburg monarch, Emperor Charles VI, designated him as new bishop of Făgăraș. On 5 September 1729 he was awarded the title of Baron, and on 23 September of that year, Micu became a priest and immediately he joined the Basilian Order. Pope Clement XII confirmed him on 11 September 1730, and accordingly he was consecrated a bishop on 5 November 1730 by Gennadius Bizanczy, the Eparch of Mukachevo. From Mukachevo he moved to Vienna, where he pleaded the Emperor for the rights of Transylvanian people. He made his formal enthronement in Făgăraș on 28 September 1732, and, following his insistence, on 11 December 1732 he was given a seat in the Transylvanian Diet. Immediately after his enthronement, he summoned an ecclesiastic synod which issued 20 decrees on administrative, disciplinary, sacramentary issues. In 1737, he moved the bishopric seat from Făgăraș to Blaj, and laid the foundations to the local cathedral in 1741. File:Ep Inocentiu catre Card Millini.jpg|thumb|left|upright|Letter with signature: Joannes In L B Klein Vescovo di Fogarasi As a member of the Diet of Transylvania, Inocențiu Micu began to press the Habsburg Monarchy to fulfill the Agreement that conversion to Greek Catholicism would bring with it Roman Catholic-like privileges for Romanian inhabitants also, and an end to serfdom. First pressing for rights for clergy and converts, he soon began to petition for freedom for all Romanians. Micu petitioned the Habsburg court for over forty years to this end. His perseverance ultimately made both the Austrian Empress Maria Theresia and Transylvania's Diet declare themselves offended - the Hungarian majority in the Diet opposed the liberation of the work force or the awarding of political rights to Romanians, considered by the Diet as "moth for the cloth". Exiled in 1744, Micu moved to Rome and he had to resign a few years later, on 7 May 1751. He died in Rome 17 years later, on 22 September 1768.
