Hence, early pan-Slavic language projects aimed at modernizing Old Church Slavonic and adapting it to the needs of everyday communication.  Early projects. The first pan-Slavic grammar, Gramatíčno izkâzanje ob rúskom jezíku by the Croatian priest Juraj Križanić, was written in 1665.
Because Old Church Slavonic had become too archaic and complex for everyday communication, Pan-Slavic language projects have been created from the 17th century onwards in order to provide the Slavs with a common literary language. Interslavic in its current form was standardized in 2011 after the merger of several older projects.