Prologue

      When I was a child my grandmother used to call me a Mongolian. In memory the word evokes the scent of grass and of fallen leaves, some atmosphere of twilight and of horses.

      My grandmother lived at the top of an Irish village with views southwards to the Mountains of Mourne. In the evenings, in the long dusk that my grandmother called ‘daylegone’, I played on a raised pavement that ran along the churchyard wall, beneath an arch of lime trees. They were solitary and elaborate adventures involving horses and culprits. My stallion pranced through swathes of freshly mown grass and piles of autumn leaves. We leapt the wall in a single bound.

      When it grew dark my grandmother would call me home, her voice looping in the lingering twilight like a rope. I resisted as long as I could, galloping between the trees in the thickening gloom, against the tug of her voice. When she stopped calling I sat in thrones of leaves gazing to the south where the Mountains of Mourne shouldered the horizon. The mountains were dark and mesmerizing, the frontier to the wide world of County Down. My father said that beyond the mountains lay the sea.

      When the long lasso of my grandmother’s voice came again my horse was already melting away between the graves. I turned home, and presented myself in the back hall with skinned knees and leaves in my hair. As my grandmother bent over me to brush and straighten my clothes, she always said the same thing. ‘Like a Mongolian,’ she sighed. ‘Just like a little Mongolian.’

      I never heard anyone else speak of the mysterious Mongolians, and I had no idea who they were. I recognized the word was an admonition of sorts but I sensed it also contained a note of praise. I liked its unruliness and its ambiguities, and I wanted to live up to the idea of recklessness that it seemed to imply.

      Long before I had any clear sense of Mongolia as a place, the word belonged to those intense adventures played out each evening in the slow descent of an Irish twilight, as I tugged against the mooring of my grandmother’s voice calling me home.

      It was in Iran, twenty-five years ago, that I first saw nomads. I was part of an expedition looking for the Persian Royal Road. Led by a charming charlatan who was a cross between Rommel and W.C. Fields, our small and happily deluded team spent eighteen months in the field, rattling around Anatolia and the Zagros mountains with a couple of Land Rovers, a leaky tent and a copy of Herodotus. It was the best of journeys. The landscapes were magnificent, the people hospitable and we had the alibi of historical purpose.

      In the Marv Dasht plain beneath the