Linguistic investigation began during the 19th century, although the research itself often ended in non-linguistic or outdated conclusions. Since that was the age of national revivals across Europe as well as the South Slavic lands, the research was steered by national narratives. Within that framework, Slovene philologists such as Franz Miklosich and Jernej Kopitar attempted to reinforce the idea of Slovene and Kajkavian unity and asserted that Kajkavian speakers are Slovenes. On the other hand, Josef Dobrovský also claimed linguistic and national unity between the two groups but under the Croatian ethnonym.