Although it is often suggested in the literature on historical syntax that a translated text may be influenced by its source language, there is little work that has examined the nature of this potential interference in detail. This paper provides a comparative analysis of the Middle English prose Brut and an Anglo-Norman version of the same text in order to determine the way in which the Anglo-Norman source text may have influenced the syntax of the Middle English version. The focus is on two syntactic phenomena with respect to which the Middle English Brut differs from other texts from the same period, namely adverb placement and the placement of object pronouns. Whereas in the first case no link to the Anglo-Norman source can be established, the second distinctive property is most plausibly accounted for in terms of language contact. However, the Middle English translator does not slavishly follow the syntax of the source. This is shown most clearly by the fact that he generally avoids an Anglo-Norman word order that can be considered as ungrammatical in late Middle English. The effects of contact are largely of a quantitative nature. Word orders that are only marginally present in other late Middle English texts occur with high frequencies in the Middle English Brut. These findings confirm that translation effects must be seriously considered as a potential source of interference at least in quantitative diachronic studies.