English exerts great influence on other languages at the lexical level, as seen from extensive borrowing of terminology and everyday words into many languages (i.e. Anglicisms such as swap, blog, etc.). Although much less studied, it is also clear that the “phrasicon” (Granger, Sylviane. 2009. Comment on: learner corpora: A window onto the L2 phrasicon. In Andy Barfield & Henrik Gyllstad (eds.), Researching collocations in another language. multiple interpretations , 60–65. Houndmills: Palgrave Macmillan) of a language can similarly be affected by such external influence. This paper investigates “the largely unexplored area of phraseological borrowing” (Fielder, Sabine (2017) Phraseological borrowing from English into German: Cultural andpragmatic implications. Journal of Pragmatics 113: 89–102, 90) by introducing the diachronic-contrastive corpus method and exemplifying it with reference to a set of expressions that have been considered the products of language contact between English and Norwegian. I argue that the proposed corpus method can be used efficiently for investigating phraseology across time, for shedding light on the question of whether cross-linguistically parallel structures are the result of borrowing or parallel developments, and – importantly – as a vehicle for rejecting preconceived ideas about a form’s alleged origin in English.