Maslenitsa (also known as Butter Lady, Butter Week, Crepe week, or Cheesefare Week) is an Eastern Slavic religious and folk holiday, which has retained a number of elements of Slavic mythology in its ritual, celebrated during the last week before Great Lent, that is, the eighth week before Eastern Orthodox Pascha.
The date of Maslenitsa changes every year depending on the date of the celebration of Easter. It corresponds to the Western Christian Carnival, except that Orthodox Lent begins on a Monday instead of a Wednesday, and the Orthodox date of Easter can differ greatly from the Western Christian date.
The traditional attributes of the Maslenitsa celebration are the scarecrow of Maslenitsa, sleigh rides, festivities. Russians bake bliny and flatbread, Belarusians and Ukrainians cook pierogi, syrniki.
According to archeological evidence from 2nd century A.D. Maslenitsa may be the oldest surviving Slavic holiday. In the Christian tradition, Maslenitsa is the last week before the onset of Great Lent.
During the week of Maslenitsa, meat is already forbidden to Orthodox Christians, and it is the last week during which eggs, milk, cheese and other dairy products are permitted, leading to its name of "Cheese-fare week" or "Crepe week". The most characteristic food of Maslenitsa is bliny - thin pancakes or crepes, made from the rich foods still allowed by the Orthodox tradition that week: butter, eggs and milk.
Since Lent excludes parties, secular music, dancing and other distractions from spiritual life, Maslenitsa represents the last chance to take part in social activities that are not appropriate during the more prayerful, sober and introspective Lenten season.
In some regions, each day of Maslenitsa had its traditional activity. Monday may be the welcoming of “Lady Maslenitsa”. The community builds the Maslenitsa effigy out of straw, decorated with pieces of rags, and fixed to a pole formerly known as Kostroma. It is paraded around and the first pancakes may be made and offered to the poor. On Tuesday, young men might search for a fiancée to marry after Lent. On Wednesday sons-in-law may visit their mother-in-law who has prepared pancakes and invited other guests for a party.
Thursday may be devoted to outdoor activities. People may take off work and spend the day sledding, ice skating, snowball fights and with sleigh rides. On Friday sons-in-law may invite their mothers-in-law for dinner. Saturday may be a gathering of a young wife with her sisters-in-law to work on a good relationship.
According to en.wikipedia