This paper considers the role of historical context in initiating shifts in word meaning. The study focusses on two words – the translation equivalents separatist and separatism – in the discourses of Russian and Ukrainian parliamentary debates before and during the Russian–Ukrainian conflict which emerged at the beginning of 2014. The paper employs a cross-linguistic corpus-assisted discourse analysis to investigate the way wider socio-political context affects word usage and meaning. To allow a comparison of discourses around separatism between two parliaments, four corpora were compiled covering the debates in both parliaments before and during the conflict. Keywords, collocations and n-grams were studied and compared, and this was followed by qualitative analysis of concordance lines, co-text and the larger context in which these words occurred. The results show how originally close meanings of translation equivalents began to diverge and manifest noticeable changes in their connotative, affective and, to an extent, denotative meanings at a time of conflict in line with the dominant ideologies of the parliaments as well as the political affiliations of individuals.