25 November, International Day for the Elimination of Violence Against Women

  Officially recognised by the United Nations since 1999, when it declared 25th November as International Day for the Elimination of Violence Against Women, White Ribbon Day first originated in 1960.  It was on this day, 49 years ago, that three sisters in the Dominican Republic, all political activists and campaigners for equal rights, were murdered by people working for the fascist government they opposed.  Since then the sisters – Patria, Maria and Minerva Mirabel – have become symbols of dignity and inspiration around the world:
July 1981
Women from across Latin America came together in Columbia. Appalled by the extent and diversity of violence against women, they agreed to hold an annual day of protest, and they decided to adopt 25th November as the date for this International Day Against Violence Against Women in memory of the Mirabel sisters.
1991
The first White Ribbon Campaign was launched by a group of men in Canada after the brutal mass shooting of 14 female students at the University of Montreal.
1996
In South Africa the National Network on Violence Against Women launched their own White Ribbon Campaign and many South African womens groups quickly adopted the White Ribbon symbol.
1998
WOMANKIND launched the first White Ribbon Day in the UK.
1999
The UN officially recognised 25th November as International Day for the Elimination of Violence Against Women.
The White Ribbon is a symbol of hope for a world where women and girls can live free from the fear of violence. Wearing the ribbon is about challenging the acceptability of violence by getting men involved, helping women to break the silence, and encouraging everyone to come together to build a better world for all.

Source: http://www.whiteribboncampaign.co.uk/FAQs