Peoples who seem to date from another time and another place -- Mandeans who worship John the Baptist, Assyrians, Turkmen -- still inhabit forgotten pockets, caught in an eddy as history swirled on.

The fact that Yazidis have long clung to their microreligion amid far larger concentrations of Christians and Muslims testifies to the ferocity of belief in this region. Indeed, its agglomeration of peoples and faiths is one reason Iraq is considered a fractious place, difficult to govern.

The village of Bashiqa, home to 5,000 people, sits where the Mosul plain meets the plump foothills of the Maklub Mountains. Its Chaldean Catholic church, mosque and Yazidi temple sit within hailing distance of each other.

Surrounding olive groves produce the sacred oil for Yazidi temple lanterns, and distinctive, conical Yazidi tombs dominate the hills. The metal ball topping the tall skinny dome of the pale sandstone tombs represents the sun, and 12 vertical stone ridges radiating down from the ball represent its hallowed rays and the hours of the day.

The Yazidis, who are ethnically Kurds, maintain one of the most eclectic of faiths.

They have adopted Christian rituals like baptism and a smattering of practices from Islam ranging from circumcision to removal of their shoes inside their temples. The importance of fire as a divine manifestation comes from Zoroastrianism, the ancient Persian faith that forms the core of Yazidi beliefs. Indeed their very name is likely taken from an old Persian word for angel.

The veneration of their saints' tombs means few Yazidis have ever wandered far from their Iraqi roots, although there are branches in Turkey, Syria, Iran, the Caucasus and, because of modern migrations, Germany. Estimates on their numbers swing wildly, but are generally put around 300,000 in Iraq.

Yazidis venerate Sheik Adi bin Musafir, a 12th-century Lebanese-born Arab mystic whose tomb, in Lalish in northern Iraq, is their main place of pilgrimage. They say Sheik Adi revived a faith dating back to Adam.