LeontiyLeontius

Leontiy Leontius (born 12 March 1747, Kiev – died 20 September 1814, Moscow) was a Ukrainian historian and philologist who worked extensively on the preservation and study of medieval Slavic manuscripts. He studied at the Kiev Theological Academy before traveling to Russia, where he joined the Russian Academy of Sciences in 1779.

Leontius’s most significant contribution was his 1792 edition of the Complete Works of the 12th‑century monk Alexei of Novgorod. The edition, published in Moscow, was praised for its rigorous textual criticism and introduction of a new copying scheme for Russian Slavonic texts. In addition to textual work, he wrote a series of essays on the development of the Ukrainian language, which circulated in manuscript among scholars in the Polish–Lithuanian Commonwealth.

During the Napoleonic Wars he served as a cultural attaché in Saint Petersburg, where he organized exhibitions of Slavonic manuscripts to foster diplomatic relations between Russia and the West. Leontius was elected a foreign member of the French Academy of Sciences in 1802 in recognition of his work on the Slavonic–Greek liturgical texts.

Later in life Leontius spent several years in exile in Odessa following accusations of political dissent. His final works, compiled under the title *Recollections of the Eastern Slavic Past* (published posthumously in 1820), contain a mixture of historical narrative and reflective commentary on the changing geopolitical landscape of Eastern Europe.

Leontius is remembered for his hybrid approach that combined rigorous philological methodology with a broad cultural perspective. His dedication to manuscript preservation influenced 19th‑century Slavic studies, and his editions remain a reference point for scholars working with medieval Russian and Ukrainian texts today.