This paper focuses on Croatian grammar books published between 1945 and 1990. That corpus includes "Gramatika hrvatskoga ili srpskog jezika" (1952) by Brabec, Hraste, and Živković, "Kratka gramatika hrvatskosrpskog književnog jezika" (1964) by Jonke, "Pregled gramatike hrvatskosrpskog jezika" (1966) by Težak and Babić, "Kratka gramatika hrvatskosrpskog književnog jezika za strance" (1967) by Hamm, "Gramatika" of the "Jezični savjetnik" (1971) by Pavešić and Vince, and "Priručna gramatika hrvatskoga književnog jezika" (1979) by Barić et al. Throughout that period, linguistic-political events were complex and tumultuous, particularly marked by the relationship between the Croatian and Serbian standard languages. The implementation of language unitarization and attempts to create a Croatian-Serbian standard language were at full strength; on the other hand, gradually, over time, there was a more obvious effort to establish the literary-linguistic paradigm and search for one’s linguistic peculiarities. With that in mind, the paper discusses the sociolinguistic context of the abovementioned grammar books. Primarily, their normative status is observed by considering official proclamations, agreements, and statements regarding the Croatian language and the State Regulation on Education that have impacted it. Grammar rules are analysed by comparing selected sections that caused disputes in terms of clarity or created difficulties for speakers of the Croatian language. In particular, the role of certain grammar books in the standardization process of the Croatian language is considered in this context.