The original names of the months of the year in the Slavic languages closely follow natural occurrences such as weather patterns and conditions common for that period, as well as agricultural activities.
While subject to variation over the earlier centuries, their names and order have been standardised in 1830s through the efforts of the Illyrian movement and its chief linguist Vjekoslav Babukić.
However, there is also a set of older names for the twelve months of Slavic origin that differ from the Latin month names, although their usage is archaized and largely restricted to folk literature and religious calendars issued by the Macedonian Orthodox Church.
The usage of modern Latin month names among Macedonians started towards the end of the 19th century, as a result of mass education.
The names of Polish months are, as in Belarusian, Croatian, Czech, Kashubian, and Ukrainian, not based on the Latin names used in most European languages, with the exception of March and May, which were borrowed from the Gregorian calendar.