Slavic tribes did not use the Roman calendar for a long time. The pagans, whose life was subject to the solar-lunar cycle, lived from sowing to harvest, which was reflected in the Slavic names of the months.
Old Slavic calendar
The calendar of the ancient Slavs did not correspond to the modern one. However, no one knows exactly what he was. According to some scientists, the month, or the moon, lasted 28 days, the year consisted of 13 such months. Other researchers believe that the 13th month was added from time to time, as the calendar lagged behind the actual seasonal changes. Still others are convinced that the calendar consisted of 12 months, but they were significantly different from modern ones.
In addition to the western and southern Slavs, the Lithuanians used the Slavic names of the months. The fact is that during the period of Balto-Slavic unity, the culture and languages of the Slavic and Baltic peoples became closer.
For a long time, the beginning of the year was considered spring, later - the beginning of autumn, the harvest season. After the adoption of Christianity by the Slavs, the calendar began to correspond to the Roman Julian calendar. The Slavic names of the months began to be applied to the months of this calendar, and in places they were replaced by Roman ones. However, among the common people, the Roman months did not take root immediately, and in some places they are not used to this day, for example, in Ukraine, Poland, Czech Republic, Croatia, Slovenia, Macedonia and some other Slavic states.
November among the Slavs
Among the ancient Slavs, the period falling in November was called "leaf fall", since at this time the leaves began to fall from the trees. After the division of the Slavic tribes into southern, western and eastern, the names of the months also changed. For some Eastern Slavs, the November period began to be called "oats" because of the harvesting of oats at that time, and among the southern Slavs - "cold" because of the cold weather coming in November.
Gradually, in various Slavic countries, their names for the months were established. Most of the Slavic names for November come from the ancient word "leaf fall". This is how November is called in Ukrainian, Belarusian, Czech and Polish. Among the southern Slavs - Croats, Bulgarians and Macedonians - the word "studen" has taken root. Gradually in the Bulgarian language it began to mean December, and November began to be called "breast". Then both the Bulgarians and the Macedonians switched to the generally accepted names for the months, and “breast” gave way to the name “noemvri”.
Of the countries with a traditionally Orthodox culture, the Slavic names of the months remained in Ukraine and Belarus. Of the countries where Catholicism prevailed, the names from the Slavic calendar remained in Croatia, the Czech Republic and Poland.
Old Russian "oat" gradually disappeared from the language, along with little-used names such as "rotten" and "leaf-bearing". Now these names can only be found in the works of linguists.