In November 1873, he was elected Bishop of Arad, and was enthroned in February 1874.
Elected Archbishop of Sibiu and Metropolitan of Transylvania that November, he was enthroned the following month and remained in office until his death.While a professor of theology, Romanul wrote several textbooks that remain in manuscript.
He wrote for the Sibiu-based Telegraful Român and for the Pest Concordia and Federa?iunea.
Active within Asocia?ia na?ionala aradeana pentru cultura poporului român, he was at the forefront of the Arad Romanian National Party organization and was elected to the Diet of Hungary's House of Representatives in 1869.
As metropolitan, he sat in the House of Magnates, where he defended Romanians' rights on a number of occasions, in particular intervening on behalf of their confessional schools in 1879 and 1883.
He guided the activity of the theological-pedagogical institute and helped finance the education of numerous students, offering them scholarships from the metropolis' funds or from endowments it managed (such as that left by Emanoil Gojdu).
During his reign, new archdiocesan buildings were constructed.
In April 1896, he sent out a circular urging his clergy and faithful not to participate in Hungary's millennium celebrations.