The fact that Thucydides uses chronology dividing the year into summer and winter may be explained not only by the obvious necessity to separate the period of active hostilities (summer Gepoq, including spring and autumn) from the period when military operations were only occasional (winter). This kind of chronological distinction could have had more personal reasons: as strategus Thucydides failed to defend Amphipolis because of swift and sudden winter march of Spartans led by Brasides. Thucydides stayed on Phasos (known for its kind climate), hopelessely far away from the theatre of war; active military operations in winter, in the snow, in the «severe land» of Khalkidike (II. 70. 2) seemed hardly possible to him. Thucydides the historian was eager to account for, if not to excuse, the failure of Thucydides the general. The introduction of «winter campaign» as a chronological unit fitted his intention very well; the strategos had acted correctly, according to the tradition, while Brasides broke it, not respecting the rules of normal warfare. It was no mere chance that Thucydides' division of the year into winter and summer proved to be artificial and did not take root in later historiography. It is noteworthy how easily Thucydides' successor Xenophon gets rid of this division in his Hellenica.