Who was Alexander von Humboldt? Was he really a lone genius? Was he another European apologist for colonialism in the Americas or the father of Latin American independence? Was he a roving Romanticist, or did his sensibilities belong to the Enlightenment? Naturalist, philosopher, historian, and proto-sociologist–to name just some of the fields to which he contributed–, Humboldt is impossible to contain in a single identity or definition. His voluminous writings range across so many different fields of knowledge that his scholarly-scientific personae multiplied even during his lifetime, and they have continued to proliferate since his death in 1859. A household word throughout the nineteenth century, Humboldt was eventually eclipsed by Charles Darwin (whose own travels had been motivated by Humboldt’s) and disappeared from view for much of the twentieth century, notably in the United States. The essays in this collection testify to the renewed interest that Alexander von Humboldt’s multi-faceted work is inspiring in the twenty-first century, especially among cultural and literary historians from both sides of the Atlantic. This book was originally published as a special issue of Atlantic Studies.