The article describes the tragic circumstances concerning the army of Charles XII retreat after the defeat of the Poltava. The work based on a wide range of foreign sources: the diaries and memoirs of participants. For the first time in Russian historiography for the reconstruction of the events the author uses the diary of the superintendent of the Evangelical church in Slovakia Daniel Krman and the memories of Swedish Lieutenant Constantine de Turville. A close exploring the sources has substantially clarified the real picture of retreat, identified several previously unknown circumstances.