March 8th is the Festa della Donna in Italy - or "Woman's Day":
"Traditionally the women are given a small bouquet of mimosa - yellow flowers in a small cluster, that emit a sweet fragrance, and spend the evening without male company."
The origins are many, including:
"...memorializing two events outside of Italy: a March 8, 1857, strike by women garment workers in New York, which led to the formation two years later of the first women's union in the United States, and a strike by Russian women calling for "bread and peace" on March 8, 1917 (February 23 on the old Russian calendar but March 8 in the rest of the world.)"
If you can read Italian, see the Wikipedia entry for "Festa della donna"