Dialects of Serbo-Croatian
Kajkavian is spoken in North Croatia, including the capital Zagreb, as well as in a few enclaves in Austria, Hungary, and Romania. Though its speakers are ethnic Croats and Kajkavian is thus generally considered a dialect of Serbo-Croatian, it is closer to neighboring Slovene than it is to Chakavian or Shtokavian. The Kajkavian area of Croatia is bordered on the northwest by Slovene language territory. It is bordered on the east and southeast by Shtokavian dialects roughly along a line that was the former division between Civil Croatia and the Habsburg Military Frontier; in southwest along Kupa and Dobra rivers, it persisted in ancient (medieval) contact with Chakavian dialects.
Serbo-Croatian
The opinion of the majority of Croatian linguists is that there has never been a Serbo-Croatian language, but two different standard languages that overlapped sometime in the course of history. However, Croatian linguist Snježana Kordić has been leading an academic discussion on this issue in the Croatian journal "Književna republika" from 2001 to 2010. In the discussion, she shows that linguistic criteria such as mutual intelligibility, the huge overlap in the linguistic system, and the same dialect basis of the standard language are evidence that Croatian, Serbian, Bosnian and Montenegrin are four national variants of the pluricentric Serbo-Croatian language. Igor Mandić states: "During the last ten years, it has been the longest, the most serious and most acrid discussion (…) in 21st-century Croatian culture". Inspired by that discussion, a monograph on language and nationalism has been published.