After Marr's death, he moved to broad Iranian topics and field work in Ossetia until the end of World War II.
In 1945 he moved back to Leningrad where he published his work on the Nart sagas, a dictionary and grammar book of Ossetian.
With Joseph Stalin's condemnation of Marr's linguistic theories the Yaphetic Institute was purged, but Abaev was spared.
Starting with the 1950s, Abayev became internationally famous as the leading authority on Scythian and Sarmatian linguistics.
Assisted by his friend, Georges Dumézil, Abaev demonstrated connections between the Scythian languages and modern Ossetian.