The paper examines the changes in the offi cial language of the Petrine era from a functional point of view. Th ese changes were systematic and were due, fi rstly, to the strengthening of the role of document communication in the country’s governance and to its regulation, i.e., to strengthening the regulatory function of state communication. Secondly, they were due to the changes in the principles of state communication: in the Petrine era the basic metaphor of the state — the family metaphor that explains the structure of the state in terms of a feudal family, was replaced by a new European metaphor that understood the state as the clock (the clock metaphor). Finally, thirdly, the Slavonicisation of offi cial language, which occurred in the Petrine era, can be regarded not only as an attempt to fi nd a new code of state communication, but also as the use of Slavonicisms in the aff ecting function. Changes in the state, breaking of traditions demanded from the authorities and, above all, from the tzar Peter the Great to draw mobilizing and socializing functions of state communication.