Dissertation analyses linguistic usage of a kajkavian translator and a priest Ivan Krizmanić (1766 – 1852), who wrote the majority of his work in national language before the Croatian Revival movement, starting at the age of 43 (Palafox Generalu Lefebureu, 1809) writing in old kajkavian orthography and kajkavian literary language, translating to it from štokavian as well. In the mid 1830's Ivan Krizmanić met and befriended many Illyrians, and in his work created between 1835 and 1841 he changed visual identity of the language by adopting Gaj's orthography, even though he was still writing in kajkavian literary language. Finally in 1842, when Illyrianism became a political program, and Illyric štokavian language had already been described in two grammars and in a dictionary, Krizmanić at the age of 76 altered his language identity and started writing in Illyiric štokavian (Pogor u Rimu, 1843), translating to it from kajkavian (Ogenj vu Rimu, 1820). Using the interdisciplinary approach based on interweaving of history, sociology and linguistics, the analysis is conducted on two basic levels. On a macro level we explore social history of kajkavian literary language, i.e. its status and role in multilingual society of the Northwestern Croatian during the first half of 19. Century. Historical and social events, such as the French revolution and an idea of using national language which the revolution promoted as well as the development of a civil society and Illyrism in the 1830's, are also observed. The paper also analyses the impact of Illyrian efforts on implementation of national language based on štokavian grounds on linguistic identity of the kajkavian author Ivan Krizmanić and on his choices of the linguistic code. On a micro level we observe variability of Krizmanić's linguistic use in kajkavian corpus on orthographic, phonetic and morphologic level with the aim to link linguistic and social variation. Variation is analyzed inside certain texts as well as in the entire corpus, and Krizmanić's linguistic variables are compared to grammatical description of Ignac Kristijanović. By comparing a language use and grammatical norm between the two contemporaries, the aim is to establish a degree to which kajkavian literary language is standardized over the last decades of its existence.