Sobolevsky Aleksey (1856‒1929) – linguist, paleographer, specialist in Slavic studies, social activist. Brother of Sergey Ivanovich Sobolevsky.

In 1874, he enrolled to the Historical and Philological Faculty of the Moscow University; after it taught at the High Female Courses. In 1882, he defended his Master thesis ‘Research in the Field of Russian Grammar’, and was invited to the Chair of Russian Language and Literature of the Kievan St Vladimir University. In 1884, he defended his Doctor thesis ‘Essays on the History of Russian Language’, and became Full Professor of the Kievan University. In 1888-1908, he was Head of the Chair of Russian Language and Literature at the St. Petersburg University. In 1908, he retired and returned to Moscow, where he headed the Commission on composing the ‘Dictionary of Old Russian Language’.

Correspondent Member (1893) and Academician of the Ac. of Sc. (1900). Correspondent Member of the Beograd and Sophia Ac. of Sc. In 1916, he was a member of the State Council. Member of the Orthography Commission, he took part in the reform of Russian orthography in 1918. Member of the Imperial Orthodox Palestinian Society. Monarchist, active participant of the Union of Russian People (one of the so called ‘black hundred’), member of its council and Deputy Chairman.

In the summer 1918, he was arrested, but was released on bail and stayed under a ban to go away.

Since October 1925, S. was Head of the Commission on composing the ‘Dictionary of Old Russian Language’ in the system of the Ac. of Sc. In 1925-1929, he made lexicographical research. He died in 1929; was buried on the Vagan’kovskoe Cemetery in Moscow.

He wrote more than 400 research works; for the history of religion he has a significance for his studies in folklore, ethnography, and Slavic antiquities.