International Women's Day feels more necessary, potent and significant this year than ever. Just six weeks since women marched for our rights on every continent on earth, there's a sense of the day reasserting its roots in protest.
The inspiration for International Women's Day takes us back to 1908, when 15,000 garment workers marched through Manhattan, protesting for shorter working hours, improved pay and the right to vote. Today, in the US and beyond, the spirit of that guiding strike will be evoked in A Day Without a Woman, a protest organised by the Women's March, in solidarity with the International Women's Strike. They are calling for women to take the day off from paid or unpaid work; to avoid shopping for the day (unless buying something from a small, women- or minority-owned business); and/or to wear red in solidarity.
There's the sense of a major movement currently under way, a reassertion and realignment of feminism that is inclusive and serious about tackling economic inequality, job insecurity, reproductive rights, immigrant rights, violence against women, and many other issues. I've been reading and thinking widely about feminist history over the last year, while writing the book Modern Women, a series of profiles of 52 women who helped shape our modern, progressive values. All of the figures in the book are impressive, whether that's Katharine Hepburn with her twelve Oscar nominations and sunny, emancipated aggression; Bjork with her musical genius and experimental drive; or Frida Kahlo, with the arresting self portraits which created a new iconography of womanhood.
But when thinking about the women I find most inspiring, I realised there was a defining quality - all had put themselves on the line for a bigger cause.
Some are women who define specific feminist eras. So, for instance, I profiled Sophia Duleep Singh, the goddaughter of Queen Victoria, who became a leading figure in what is sometimes called the first wave of feminism, the struggle for women's suffrage. Singh threw herself into this - quite literally when she hurled herself at the car of Prime Minister Herbert Asquith in 1911, pulling a banner from her fur muff that read "Give women the vote!".
As described in Anita Anand's essential biography of Singh, she had joined the Women's Social and Political Union (co-founded by Emmeline Pankhurst) in 1908, and went on to become part of the tax resistance movement the year afterwards - women who refused to pay taxes on the basis there should be no taxation without political representation. She marched on parliament on 18 November 1910, in what became known as Black Friday - suffragettes brutalised and molested by police and the crowds. And she was also involved with the suffragette action to subvert the census, one of thousands of women who stayed out on the night of the count, because 'if women don't count, neither should they be counted".
I wrote about Gloria Steinem and Dorothy Pitman Hughes, leading figures in the second wave feminist movement of the late 1960s and 1970s, who toured the US speaking about women's liberation, at a time when women in that country and across the world were meeting in consciousness-raising groups to define the issues that most affected them - then setting up women's refuges and Rape Crisis centres, and protesting for equal pay and reproductive rights.
There are women throughout the book who have risked their lives in order to speak out. The Kenyan environmentalist and pro-democracy activist Wangari Maathai, for example, who was confronted by guards in the late 1990s, as she planted a tree in Karura Forest, in protest at the land being given to developers and government allies. In her 2006 autobiography Unbowed, she describes being left with a serious head wound; she signed the formal complaint of assault with an X, in her own blood.
The musician Nina Simone faced death threats for her civil rights activism, expressed in songs including 1964's Mississippi Goddam; the singer Miriam Makeba spent thirty years in exile from her home country of South Africa due to her determination to stand up to apartheid; the journalist Ida B Wells was exiled from the state of Memphis, and lost the newspaper she part-owned and edited, because of her stance against lynching; and Lee Miller, the only female photojournalist to have seen combat during the Second World War, lived, for the rest of her life, with the trauma of having borne essential witness to the horror of Dachau and Buchenwald concentration camps.
The activist Leymah Gbowee put herself on the line when Liberian peace talks, held in Ghana, were failing, by gathering 200 women to barricade the exits. The delegates would just have to stay and talk. When a security guard accused Gbowee of obstructing justice she began to strip, explaining in her memoir that this involved summoning up a traditional power: "In Africa, it's a terrible curse to see a married or elderly woman deliberately bare herself". An official stopped her, and the talks thereafter proceeded at a new pace.
Sophie Scholl, the German student who spoke out against the Nazis as part of the White Rose resistance group, was executed as a result, aged 21. Even at her trial, she refused to be cowed. This International Women's Day and beyond, speaking up for the rights of those most in need, we must try, as best we can, to summon a little of the courage of Sophie Scholl.
Modern Women, by Kira Cochrane, is published by Frances Lincoln, an imprint of The Quarto Group.
HuffPost UK is running a month-long project in March called All Women Everywhere, providing a platform to reflect the diverse mix of female experience and voices in Britain today
Through blogs, features and video, we'll be exploring the issues facing women specific to their age, ethnicity, social status, sexuality and gender identity. If you'd like to blog on our platform around these topics, email ukblogteam@huffingtonpost.com