Saddam Hussein's use of chemical weapons against Iraqi Kurds in the 1980s was cited by Western powers as one of the justifications for the 2003 invasion that toppled him.
Once again, the perilous situation of the Kurds - this time attacked by Islamic State fighters - has spurred the United States and its allies in Europe and the Gulf to use military force in Iraq and Syria.
8 Apr 1991 . Cukurca, Turkey. REUTERS/Srdjan Zivulovic
Reuters photographers have chronicled Kurdish refugee crises over the years. Pictures from 1991 show men, women and children carrying their possessions, gathering firewood and burying their dead in a refugee camp in Cukurca, Turkey, just across the border from Iraq.
They had escaped a military operation by Saddam's government aimed at "Arabising" Kurdish areas in the north. Hundreds of thousands fled into Turkey and Iran.
25 Sep 2014 . SURUC, Turkey. REUTERS/Murad Sezer
Now, once again, the Kurds — as many as 30 million people spread through Turkey, Iraq, Syria and Iran, but with no state of their own — are on the move. Usually far from the headlines, whole families have trekked away from danger.
Since the fall of Saddam, the Kurds' semi-autonomous region in northern Iraq became, until the Islamic State offensive that started in Iraq in June and turned against the Kurds in August, a haven of relative peace in a war-ravaged country.
8 Apr 1991 . Cukurca, Turkey. REUTERS/Srdjan Zivulovic
The attacks by the militants — who are notorious for killing anyone who refuses to convert to their austere version of Sunni Islam — created a new wave of refugees, from Iraq and Syria.
Most Kurds are Sunni Muslims, but tend to feel more loyalty to their Kurdishness, rather than their religion.
25 Oct 2014 . SURUC, Turkey. REUTERS/Kai Pfaffenbach
Reuters pictures taken in a refugee camp in Suruc, Turkey in recent months show familiar scenes - a line of people stretches into the distance as they walk from their homes in Kobani, across the border in Syria, where Islamic State has besieged the town.
The battle for Kobani has become a focal point, not just for the plight of the Kurds, but of the West's confrontation with global Islamist militancy.