The black cinders blanketing the ground remain from the eruption of nearby Sunset Crater volcano some time between 1040 and 1100. The settlement of Wupatki followed but it's uncertain if there was a direct cause and effect.
People may have been drawn by the eruption and stayed. Or, perhaps those displaced by the eruption moved to this lower elevation. However, as many as three generations may have passed before anyone decided to live here.
We do know that ash from the eruption, in a thin uniform layer, retained precious soil moisture providing a window of improved farming potential in this semi-arid landscape.
Meghann M. Vance, Northern Arizona University Anthropology Laboratories