The prayerstone hypothesis, grounded in Southern Paiute oral history, holds that selected incised stone artifacts were votive offerings deliberately emplaced where spiritual power (puha) was known to reside, accompanying prayers for personal power and expressing thanks for prayers answered. Proposing significant and long-term linkages between Great Basin incised stones and overarching Shoshonean cosmology, this article explores the prayerstone hypothesis in the context of the 3,500 incised stones documented from the Intermountain West, an assemblage spanning seven states and seven millennia. Employing object itinerary perspectives, it becomes possible to develop ritualized cartographies capable of matching oral Shoshonean traditions with specific geographic indicators. The results demonstrate that many (but not all) such incised stones are consistent with the votive emplacement of prayerstones. Multiple constellations of prayerstone practice operated across the Great Basin for more than 5,000 years and carried forward, without perceptible break, among several (but not all) Numic-speaking populations of the ethnohistoric interval. The diversity and antiquity implied by the prayerstone hypothesis suggest dramatically more complex cultural trajectories than those of Lamb's (1958) widely accepted model of a single, late, and simultaneous Numic spread across the Great Basin.