Although Stjepan Babić is often mentioned as a fighter for the Croatian language, there has been little research done on how exactly he fought those battles. The aim of this paper is therefore to describe his character and the way he worked during the second Yugoslavia. This is based on both known and lesser-known sources. After the introduction, the second chapter is mainly based on his autobiography and singles out and interprets information about his childhood and early youth which significantly impacted him. The third chapter presents, based on selected published data supplemented with parts of Babić's diary, the way his professional activity was conducted. The conclusion summarizes the most important findings about his way of working for the cause of the Croatian language based on this paper. Babić's knowledge of the communist system enabled him to succeed in his profession and to work towards preservation of the Croatian language, despite not joining the Communist Party. He knew how to appear harmless in a system that was scouting everywhere for enemies that needed to be removed. In times of greatest pressure, he (sometimes just seemingly) hid his true intentions by using the obligatory politically prescribed name of the language. This can be revealed by carefully reading and thinking about what he wrote. He did not fight for the Croatian language by directly revealing his views to the public, but usually indirectly through professional, scientific, and popular science work, in which his productivity was one of his weapons in the struggles for the Croatian language.