Dmytro Ivanovych Bahalii (Ukrainian: Дмитро Іванович Багалій, Russian: Дмитрій Ивановичъ Багалѣй; 1857-1932) was a Ukrainian historian and public and political figure, one of founding members of the National Academy of Sciences of Ukraine, and a full member of the Shevchenko Scientific Society since 1923.

For his master's degree, he wrote "History of the Seversk Land", reworking an essay that had been awarded a gold medal.

In one of them, he defined the Chernihiv and Poltava regions as "the core of the former Seversk land," which, from the mid-17th to the second half of the 18th century, "became the ethnographic center of the Little Russians."

He, along with historian and ethnographer P. S. Yefimenko, founded the Kharkiv Historical Archive, which supplied documentary resources for the Society's research.

Under his leadership, and owing to the work by Dmytro Doroshenko and his colleagues, the archive's funds grew becoming a powerful scientific base for research on the history of Slobozhanshchyna, Left Bank Ukraine.

A school of historian-archivists was formed, including notable figures like M. Bakay, M. Plokhinskyi, O. Radakova, D. Miller, V. Barvinskyi.

During this time, Bahalii also became an honorary member of many provincial archival commissions, including those in Tambov (1887), Oryol (1889), Tavrii (1890), and Chernihiv (1897), among others.

At the invitation of the chief commander of the Black Sea and Azov fleets, he gave lectures naval officers in Nikolaev.

Bahalii attributed the library's success to its public character, collegial management, democratic traditions, and support for initiative and creativity.

He viewed the high level of societal readiness for the spread of library services, enlightenment, education, and cultural development as a model for implementation in his own country.

To achieve this goal, he advocated for opening a cheap third tier, operating a season ticket system, establishing branch offices (especially in working areas), and ensuring the universality of the library's collection.

He believed that the library's diverse collection of artistic, popular science, and scientific literature helped readers develop intellectually and spiritually, enabling them to attain higher educational levels.

The selection of books for the HGB collection was overseen by the Board, which considered proposals from subscribers, reading room users, and staff of the third-tier library.

He was a full member of the Archaeographic Commission of the Central Archival Administration of the Ukrainian SSR and the scientific editor of the journal Arkhivna Pravo.