Early modern sources for a natural history of whales in Portugal have recently come to light as remarkably rich and varied, encompassing news reports, memoirs, poems, and treatises containing references to ichthyology.

These great cetaceans, when they stranded along the Portuguese coast or accidentally entered the River Tagus in Lisbon, aroused the curiosity of commoners, nobles, and scholars alike. Whales and the resources extracted from them were significant for food, lighting, and medicine.

Yet these vast and fascinating creatures also nourished the imagination, inspiring poems that used them as metaphors for moral reflection, while also describing the true processions of people who came to see them. From at least the eighteenth century onwards, their physical features were described in meticulous detail, with careful measurements and colour descriptions. Some written accounts were accompanied by illustrations that circulated across Europe, adapted to local contexts and translated into other vernacular languages from the Portuguese originals. In Lisbon, whales acquired a cultural existence beyond their biological life. One specimen was embalmed and mounted for royal admiration, and a large oil painting—now lost—was once displayed in the Arsenal. Written sources and iconography thus reveal that the memory of whales found expression in visual forms, serving both popular curiosity and scientific inquiry.

This document brings together a corpus of manuscript and printed sources—some previously unknown—that contain information on whales and other cetaceans recorded in Portuguese history. Each source is provided with a full reference, including archival location, a brief contextualisation of the work and its author, a transliteration of selected passages, and a summary offering interpretation and commentary.

Nevertheless, other sources may yet prove relevant to this subject, and the material presented here does not claim to exhaust research into the natural and environmental history of marine mammals in Portugal.