On 22 November 1827, Karol Józef Teofil Estreicher, historian of literature and theatre, long-time director of the Jagiellonian Library, called “the most outstanding bibliographer in the world”, was born in Kraków.

He came from an Austrian family bearing the surname Österreicher, who arrived in Poland in the 18th century and became Polonised. Karol graduated from a gymnasium in Kraków and then studied philology and law at the Jagiellonian University. He undertook work as a court applicant and notary in Krakow and Lwów. He was passionate about literature and theatre. In 1862, he was offered the post of deputy director of the library of the Warsaw Main School. He gained a doctoral degree and headed the bibliography department for four years. After returning to Krakow in 1868, he became director of the Jagiellonian Library, contributing to the enormous development of the library.

During his 37 years in office, he put it in order, modernised it, refurbished its premises in the Collegium Maius, and contributed to the expansion of the collection by 180,000 volumes, thousands of engravings, maps, and manuscripts. He also introduced new departments, for example for music items, posters, and periodicals. While working at the Jagiellonian Library, he also began work on his life’s work – the “Polish Bibliography”, an almost complete bibliography of Polish prints, published in Poland and abroad, covering the years 1470-1889. He worked independently, using only paper fiches. He collected information and described 120,000 items. He managed to publish 22 volumes of this monumental publication, which was continued after him by his son Stanisław and grandson Karol (the younger). To this day, this work remains one of the primary sources of information on Polish literature of the past centuries.

Karol Estreicher was famous for his broad research interests. He analysed the works of Aleksander Fredro, compiled a list of his works and translations by Józef Ignacy Kraszewski, dealt with the history of Polish theatre, collaborated with many periodicals, and was a co-founder of the Academy of Arts and Sciences. He prepared many biographies of Polish poets, bibliographers, and booksellers. Apart from his scientific works, he wrote poems. Estreicher also produced translations of some 30 French, German, Italian and Spanish comedies and dramas. He died on 30 September 1908 in Kraków.