The Nobel Peace Prize committee has handed out its prestigious annual award to two groups of laureates in recent years: people who were behind treaties or agreements that paved the way for peace, and inspiring individuals or groups whose work is still very much needed to address problems unlikely to be resolved anytime soon.

This year’s prize winners — Denis Mukwege, a Congolese gynecologist, and Nadia Murad, an Iraqi Yazidi — would probably fall into the latter category. Mukwege and Murad have led the way to stop the use of sexual violence as a weapon of war, but it’s hard to overstate how much more work needs to be done.

Late last year, Human Rights Watch documented how Burmese troops systematically raped Muslim Rohingya women to spread terror and fear as part of what has been condemned as a “cleansing campaign” that drove hundreds of thousands out of the country and into Bangladesh.

Holding the perpetrators accountable and preventing such acts is a “prerequisite for lasting peace,” said Berit Reiss-Andersen, Norwegian Nobel Committee chair.

But that’s a rather new international consensus, and one that is still blatantly ignored by some nations.

Doing so became at least slightly more difficult in 2008, when the United Nations finally recognized rape during conflicts as a war crime. Legally, the resolution may not have been as groundbreaking as reported at the time, given that the Nuremberg trials and subsequent tribunals in Rwanda and elsewhere had already resulted in condemnations of rape and sexual violence as crimes of war.

But the 2008 U.N. resolution was unprecedented in its scope and acknowledgment of failure. It clearly stated that sexual violence in war had “become systematic and widespread, reaching appalling levels of brutality,” because not enough was done to prevent such acts, and acknowledged the “negative impact this has on durable peace, security and reconciliation, including post-conflict peacebuilding.”

That link itself wasn’t new, given that rape had accompanied wars for centuries. But what changed in the 20th century was the emergence of a far more systematic use of it during ethnic cleansing campaigns and other conflicts — a disturbing development with effects that took decades to be fully understood.

Early on in the century, Japanese soldiers abducted hundreds of thousands of women in occupied territories and forced them into prostitution during World War II. When the war ended, the Allied forces took a number of steps to prevent a repeat of human rights abuses including rape, but sexual violence was still only mentioned as a side aspect. That changed once researchers found mounting evidence that rape itself was being used as a key weapon in the second half of the 20th century.

The European Commission found in 1996 that 20,000 Muslim girls and women had become victims of rape and sexual violence in Bosnia since April 1992, when Serb troops began bombing Sarajevo, now the capital of Bosnia. In 1996, a disturbing U.N. report detailed how Serb soldiers had “impregnated girls [who] have been forced to bear ‘the enemy’s’ child,” and that during the Rwandan genocide two years earlier, “virtually every adolescent girl who survived an attack by the militia was subsequently raped.”

In a 2003 report, Amnesty International was among the first organizations to suggest that ethnic rivalries were turning sexual violence into a strategic weapon. “In situations of inter-communal strife or conflicts drawn along ethnic or religious lines, women of a particular community or social group may be assaulted because they are seen as embodying the ‘honour’ and integrity of the community,” Amnesty wrote at the time. Other organizations, including Doctors Without Borders, were starting to notice a similar trend.

The late 1990s and the following decade brought a new awareness for the complex repercussions of sexual violence in wars that go far beyond what was acknowledged after World War II, including a rise in domestic violence. Researchers posited that men’s perceived loss of control in conflicts, if they are on the losing side, may be compensated by them resorting to domestic violence.

More than a decade before the United Nations finally took action, the organization’s own 1996 State of the World’s Children report warned that “sexual violation of women erodes the fabric of a community in a way that few weapons can,” according to a summary by UNICEF.

But more than two decades on, there are still no systematic efforts to prosecute or prevent sexual violence in war zones. This has left individual activists and groups with the harrowing mission of dealing with the fallout — in countries including South Sudan, Syria, Iraq, Burundi and many others.

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The Nobel Peace Prize awarded to two figures bringing attention to sexual violence in conflicts