 In 1918 he left for Armenia.During those years, as an artist, he participated in the excavations of Ani and copied the frescoes of the Church of the Savior (13th century), exploring the national artistic principles of Ani's monuments.After the establishment of Soviet rule in Armenia in 1920 Kojoyan, along with several other Armenian artists, was involved in the art department of "Haykavrosta" and had created agitation-propagandistic posters, caricatures, and so on according to the sample of the "ROSTA Window" (Moscow).