McNeill, William H. "What If Pizarro had Not Found Potatoes in Peru?"
Summary: Essay which points out several ways in which the potato has significantly affected history — the backing of Spain's imperial power by silver mined in the Andes, the survival of the Irish during Cromwell's invasion, and significant growth of European populations after 1750 as potato crops replaced fallowed fields — although with almost no speculation on allohistorical outcomes.
Published: In What If? 2: Eminent Historians Imagine What Might Have Been (ed. Robert Cowley), q.v.