That's not to say that ISIS isn't targeting Iraq's Christians and majority Shiite Muslims. Other religious minorities in northern Iraq, including the Kaka'is, a sister religion of Yazidism, and the Shabak, a cultural group that has some distinctive religious qualities, are also in the jihadist group's crosshairs. Instead of fleeing, some of these groups have chosen a different path: hiding. "Kaka'is are sometimes saying they're Shiites," Kreyenbroek said.
"They believe, as the Jewish people believe, that there’s a historic tendency to persecute them."
But the persecution of Yazidis in recent weeks has been particularly acute, and it's in keeping with the sect's long history. In fact, suffering has become an integral part of the group's self-narrative. "The Yazidis say they were persecuted 72 times in the past, but we don’t know. We don’t have sources until the 13th century," Şengül said. “The Yazidis became very strong in the 13th century … in northern Iraq to northern Mesopotamia, Turkish-tied Iran, and even Syria. At the same time Islam was becoming very strong in the region, so Muslim leaders started to persecute them.”
During the Ottoman era, the Yazidis faced pressure to convert to Islam, according to one 19th-century text. Some believe this is the origin of the symbolic number "72," representing the number of massacres committed by Ottoman caliphs. But again, as Şengül said, "we don't know."
In the 20th century, under former Iraqi President Saddam Hussein, the Yazidis faced killings and relocations because they are ethnic Kurds. "[They] were forced to take part in the war against Iran, and they were always sent to the front—they were the first to die," Kreyenbroek said.
Over time, these experiences have driven Yazidis to separate themselves from Iraq's Muslim communities. "This memory, the bad memories of being persecuted by Muslim leaders—it’s a reaction, a way of protecting themselves," Şengül said.
"They believe, as the Jewish people believe, that there’s a historic tendency to persecute them," Kreyenbroek observed.
This instinct to self-isolate may have contributed to the dire situation in Sinjar. "The Kurdish area in the Middle East is a mountainous area in general—and mountains protect people when they are attacked by outsiders," Şengül said. When faced with the threat of death at the hands of ISIS, the Yazidis fled to higher ground.
"It's very difficult for people to reinvent their religion without the physical presence of sanctuaries."
Now they're also fleeing from other areas of northern Iraq. In addition to the Sinjar region, many live around Dohuk, in Kurdistan. Şengül said her town in Turkey, Mardin, is seeing an influx of refugees, and others are heading to Syria. She's heard of at least three children who died on the Turkish border, waiting to cross from Iraq.
These forced migrations may further alter Yazidi identity. "They identify very, very strongly with the land," Kreyenbroek said. "The Valley of Lalish, that’s the heart of the Yazidi. It’s on the borderline of the Kurdish autonomous region, and [it's the location of] the sanctuaries of the various holy people, of the angels."
Here, "they’ve always felt secure. Sinjar, until recently, was talking about the possibility of establishing a Yazidi republic. I thought this was nonsense," he added, "but among the diaspora, it was quite seriously discussed."
The Yazidi population is heavily concentrated in Iraq, but there is a something of a diaspora in other countries—although it's impossible to know how big it is. Kreyenbroek spoke of communities in Germany, Turkey, and Holland; roughly 200 families live in the United States, half of them in Nebraska. Recently, Yazidis in Armenia tried to establish themselves as an independent, non-Kurdish ethnic group for political reasons—Armenians are still wary of Kurdish Muslims because of memories of the ethnic cleansing of Armenians that took place during World War I.
Even so, among Yazidis, "there is a very close link with the land," said Kreyenbroek. "It's very difficult for people to give it up, to reinvent their religion without the physical presence of sanctuaries and holy wells and holy groves."
Now, "the fear is that the ISIS is so close, and the first thing they would do is to destroy this holy site," Kreyenbroek said. "When that goes, that’s virtually the end of this religion."