The school was founded by the Jesuits in 1692 as a Catholic gymnasium, and Latin was the language of instruction. It was initially located in a small old building near a pharmacy on the Great Square, on the site of the present City Hall. In 1753, it moved to the upper story of a house located at the corner of what are now Mitropoliei and Samuel von Brukenthal streets. In 1773, when the Jesuits were suppressed, the school closed its doors. It reopened in 1780, when Emperor Joseph II approved its reorganization under the name Gymnasium regium Cibiniensis. The administration was composed of local Roman Catholic chaplains; the teachers were Catholic priests, who continued to offer instruction in Latin. In 1789, the school moved into the former Jesuit residence in the Great Square, adjacent to the Jesuit Church; it would remain there until 1898. The Latin period was to the benefit of local Romanian students, who comprised around a third of the student body. Among those who attended were Gheorghe Lazăr, August Treboniu Laurian, Ioan Axente Sever and Simion Balint. Change came to the school as a result of the 1848-1849 Revolution, which prompted Education MinisterCount von Thun to reorganize the gymnasiums of Transylvania in December 1849. The period of study was lengthened to eight years. In 1850, German was adopted as the main language of instruction, while Romanian was taught for the first time. In 1853, the school became a state institution under the name k. k. kath. Staatsgymnasium in Hermannstadt, while maintaining its Roman Catholic character. However, its religious affiliation was dropped in 1862. Students during the mid-19th century included Ioan Brote, Iacob Bologa, Ilie Măcelariu, Nicolae Cristea, Visarion Roman, Dimitrie Cunțan, Eugen Brote, Aaron Florian, Ioan Pușcariu, Ioan Popescu, and Sava Popovici Barcianu. Although there is no proof, it is believed that in 1864, Mihai Eminescu took his third-year gymnasium examinations here.
Lazăr has among the oldest school libraries in Transylvania. Although the date it opened is unknown, it is believed to have been operating in the second half of the 18th century. Evidence for this comes from the large collection of Latin and Greek works in rare 16th-18th century editions. Documents from 1810 to 1837 already mention the need for reorganizing the library. There are some 46,000 books in all; most are freely available to students and teachers, but 13,000 appeared before 1900 and are kept separately. The latter includes four sections, the first of which contains manuscripts, historic documents related to the political and economic life of Transylvania and correspondence from the 16th and 17th centuries, as well as old religious texts. Among the incunabula are a 1482 edition of Horace's Odes published at Florence. The rare books range from literature to philosophy, history, theology and geography. They are leather-bound, carefully printed, engraved, decorated with vignettes, scenes from antiquity, human profiles and illustrations. Finally, the collection of old Romanian books goes back to 17th-century volumes with wood covers, bound in leather and with traces of locks. These are mainly religious in character, but more secular works appear from the 18th and 19th centuries.
