Character idiolects in Henryk Sienkiewicz's trilogy were studied in the original and in two English translations by Jeremiah Curtin and W. S. Kuniczak. The method used was Burrows's technique of multivariate analysis of correlation matrices of relative frequencies of the most frequent words in the dialogue. The aim of the study was to verify the intuitions of traditional interpretations, to acquire a more comprehensive view of the phenomenon, and to obtain new insights into the nature of idiolect differentiation in Sienkiewicz. Multidimensional scaling plots for the original yielded patterns of idiolect differentiation by nationality, social status, gender, and age. Corresponding plots for the two translations preserved many of these patterns and exhibited strong similarities to each other. More studies including modified methods (including Burrows's Delta) are needed to observe further and explain why exactly patterns of similarity/difference between character idiolects are so strongly preserved in translation.