"Enough", they said.
I recall how my mother, a community leader, started and led women's clubs in my village. Women in my village organised and stood together for their rights and those of their daughters. Their lesson has stayed with me. Through their clubs, women - most of them poor - educated themselves and learned to distinguish rights from the "social norms" that culture and tradition had forced upon them.
What inspired me most about their work was the power it gave to assert their rights, and the rights of their girls, be it to education or to inherit property. And the power to say "enough" in the face of patriarchy and violence.
Some of my most painful memories are of my friends and cousins crying as they were taken away to be married to men they didn't know, often much older. I grew up seeing young girls sheltered by my mother in our house from being forced into early marriage. Those were the fortunate few.
That was many years ago and yet the same struggles endure. A half-century on, the global crisis of violence against women and girls is endemic. Around the world, one in three women will experience domestic abuse, sexual violence or some other form of violence in her lifetime.
Violence happens everywhere, across social groups and classes. Women and girls in poverty suffer most. From sexual harassment to child marriage or so-called honour killing, violence devastates the lives of millions of women and girls around the world and fractures communities. It is both a cause and a consequence of women's poverty.
There are many complex causes driving this violence against women and girls. But it is ultimately rooted in the reality that women and men are not treated equally.
Sense of entitlement
When communities share expectations that men have the right to assert power over women and are considered socially superior, violence against women and girls increases (PDF). It creates a reality whereby men can physically discipline women for "incorrect" behaviour, one where sex is a man's right in marriage.
These are examples of "social norms", the unwritten rules which dictate how we behave. They are fundamental in allowing violence against women to flourish.
Let me explain. Most people, most of the time, conform to social norms. We continuously absorb subtle messages about what is and isn't appropriate to do, say and think, from our family, our friends, our colleagues, from education, culture, the media, religion and law. These sources are not neutral. They are informed by long histories of inequalities and prejudice, and by economic and political forces.
One UN study found that, on average, men with gender discriminatory attitudes were 42 percent more likely to abuse their partners.
Our world is one in which social norms grant men authority over women's behaviour. They encourage men's sense of entitlement to women's bodies, spread harmful notions of masculinity and enforce rigid gender roles.
These norms are insidious and powerful, often transmitted through throwaway comments or casual actions: telling a woman who was raped that "she was out late at night, drunk or travelling alone and was therefore responsible for the violence" - or brushing off harmful misogyny as "locker room banter".
Formal laws may not reign here. Attitudes like these create an environment in which violence against women and girls is widely seen as acceptable, even where laws call them illegal.
Studies from India, Peru, and Brazil have linked the acceptance and approval of wife beating from individuals and communities with rates of actual violence. One United Nations study found that, on average, men with gender discriminatory attitudes were 42 percent more likely to abuse their partners (PDF).
The same study examined men's reported motivation for rape. In most countries, 70–80 percent of men who had ever forced a woman or girl to have sex said they had done so because they felt entitled to have sex, regardless of consent.
We must be aware of how social norms operate before we can change how we respond. Violence against women and girls is sustained by a net of harmful attitudes, assumptions and stereotypes. It's a net in which so many are caught: not always felt, but as strong as steel.
We can break free. We can change the harmful beliefs at the core of this problem. What was learned can be unlearned.
Oxfam is launching today a global campaign, firing up our long-standing work to End Violence Against Women and Girls.
"Enough" is the rallying cry of our campaign. I am reminded of the lessons I learned from my mother.
Our campaign will see us stand shoulder-to-shoulder with the efforts of women and men around the world already engaged in this struggle. We will support women's rights organisations especially in the global south which are already challenging harmful social norms. We will organise.
All of us can play our part. It starts with challenging and changing our own behaviour and then engaging our our families, friends, neighbours and colleagues about unequal power between men and women. Governments and public institutions - and the private sector too - must ensure their policies tackle, not accentuate, harmful social norms.
The violence that women and girls face is not inevitable. Nor will it naturally disappear. We must act! Not another girl or woman should have to suffer. This must be an urgent imperative for all of us.
Winnie Byanyima is a grassroots activist, human rights advocate, senior international public servant, world-recognised expert on women's rights, and currently the executive director of Oxfam International.
The views expressed in this article are the author's own and do not necessarily reflect Al Jazeera's editorial policy.