The son of a peasant family from Transylvania, he completed high school in Blaj, where he became a disciple of Timotei Cipariu and Ioan Micu Moldovan [ro].

He was affiliated with the Romanian Academy Library for over half a century, transforming the institution from the meager state in which he found it, and overseeing a five-fold increase of its collection.

Near the end of his life, struggling with deafness, Bianu withdrew from the Library in favor of his friend Radu R. Rosetti, but went on to serve as president of the Romanian Academy.

[6] When he arrived in 1868, the local atmosphere was uncertain and marked by the faculty's activism against the recent Austro-Hungarian Compromise, which consecrated Transylvania part of the Hungarian Crown, against Romanian demands.

[11] Bearing a recommendation from Moldovan for August Treboniu Laurian, Ioan left for Bucharest, capital of the Romanian Old Kingdom;[12] four classmates joined him in emigrating.

He still made visits abroad: in 1885, he spent time in Galicia-Lodomeria, researching the Jagiellonian Library for Romanian-related subjects, the Ossoliński archive at Lemberg, and the Dosoftei fund at Schowkwa.

He was hosted there by Antoni Wilhelm Radziwiłł, who allowed him to copy some 300 documents,[25] and befriended his young daughter Elżbieta, later wife of the Count Potocki.

[34] In addition to such work, in 1904 he served on a panel of inquiry created by the Ministry of Education, closing down the Notre-Dame de Sion schools, accused of forcefully converting Orthodox students to Catholicism.

[35] Meanwhile, a member of the National Liberal Party (PNL) and auditor of its Bucharest club,[36] Bianu was an ally of Dimitrie Sturdza and reached the Assembly of Deputies.

[37] From as early as 1887, he interceded between Sturdza and PNL-friendly academics, including the Slavist Ioan Bogdan, obtaining their support against rival Conservatives, and helping them travel for specialization abroad.

[45] In 1892, Bianu joined the executive committee of the Cultural League for the Unity of All Romanians[46] and began sending out sponsorships to the leaders of the Transylvanian Memorandum protest movement.

During the state visit to Romania of Emperor Franz Joseph, Sturdza sent Bianu, Grigore Antipa, Ștefan Sihleanu and Barbu Ștefănescu Delavrancea to Vârciorova, where they were to meet Austrian delegates ahead of the Cultural League, which sent protesters.

[52] In parallel, Bianu preserved links with the Romanians living in Russia's Bessarabia Governorate: through his correspondence with Ștefan Ciobanu, he was informed of Russification in that province.

[56] This view was instantly supported by the sociologist Dimitrie Gusti, who suggested that "Frunză's admirable work" should be published "in millions of copies, so that every Romanian will read it".

In September, shortly after the Battle of Turtucaia, he penned in Viitorul an article specifically targeting the Kingdom of Bulgaria and the Bulgarians in Romania, whom he called "venomous snakes".

"[58] The Romanian army and administration headed for Western Moldavia: Bianu's son Alexandru was drafted, but, according to his adversaries, spent the war in relative safety at Bârlad, shying away from active duty.

[58] One of ten academicians to remain behind, he ensured that the Academy Library continued to function in relatively normal terms, refusing to publish under the occupation regime,[60] but also collaborating with the occupier to at least some degree.

[67] The loyalist government was fully restored in Bucharest within a month, following the unexpected defeat of Germany, which led to the establishment of Greater Romania—which included united Transylvania from December 1, 1918.

Bianu used his intermediary position to negotiate a PNR presence at Alba Iulia, where Ferdinand crowned himself King of Greater Romania, but was unable to convince Alexandru Vaida-Voevod.

[76] Their son Alexandru studied law in Paris and returned to Romania in 1923 to work as a bank clerk, before finally joining the diplomatic corps and serving as commercial attaché in London.

[82] He continued to intervene politically for his various protegés, including the literary critic Gheorghe Bogdan-Duică and the linguist Theodor Capidan, and steered the career of philologist Alexandru Rosetti.

[85] In April 1928, during his last months at University, he seconded Rector Ermil Pangrati in urging government to dissolve the antisemitic Union of Christian Students, which was causing disturbances and riots;[86] this stance was contrasted by Vasile, who, as a member of the Senate, argued that Romanian Jews sympathized with Hungarian irredentism.

[87] His teaching hampered by a progressive deafness, which had begun much earlier in life, Bianu withdrew from the university in mid 1928, resigning his seat to his disciple, folklorist Dumitru Caracostea.

[88] The previous year, Caracostea had contributed to a Bianu Festschrift, alongside Iorga, Pușcariu, Alexandru Rosetti, Vasile Bogrea, Nicolae Cartojan, Charles Drouhet, and Petre P.

[92] An early admirer and political ally,[93] geologist Ludovic Mrazek referred to Bianu as a force of professional conservatism, one of several "decent men and sincere patriots" who stood up to intellectual fads.

[101] Encouraged by Alexandru Odobescu, Ion Ghica and Sturdza, who inspired in him an appreciation for books and libraries, Bianu renounced the idea of a scientific career in favor of working as a librarian.

He helped counter the lack of manuscripts, old books and documents on the language and national history by initiating an ample campaign for identifying and donating such materials.

[111] Likened to George Călinescu's history of Romanian literature, although more historic in aspect, it was the country's most ample bibliography at the time, praised by Iorga for its completeness.

[114] His former teacher Moldovan emerged as a steady collaborator, not only facilitating access to his library and Cipariu's diocesan collection, but also providing valuable advice over the years.

Bianu published a number of other books on early Romanian literature as well as textual editions,[105] including Psaltirea Scheiană[89] and, in 1924, the newly discovered Codicele de la Ieud.