Historians who have studied Renaissance cosmography - a discipline or practice or genre that combined elements of both astronomy and geography, and sometimes encompassed history, natural history, astrology, ethnography, and other subjects as well - have been prone to declare that it quickly disappeared. Some scholars have placed its demise as early as the end of the sixteenth century. It is my contention that such claims are erroneous, and have arisen in part because of a failure to appreciate that cosmography took a range of interrelated forms, both in the Renaissance and subsequently. I shall present evidence that 'cosmography', though apparently superseded by the distinct disciplines of astronomy and geography, enjoyed an extensive post-Renaissance life, and persisted as a scientific category in certain contexts even into the twentieth century. As well as telling us about the evolution of knowledge-making practices between and within disciplines, from 1500 onwards, study of this phenomenon raises a historiographical question. If, as I argue, 'cosmography' was still alive as an actor's category into the modern era, then can it safely be employed as a term of the historian's art for that period, as others have advocated? I shall suggest that the hazards of doing so outweigh any benefits. If we are to understand cosmography, in all its variety, we need to establish what it the term meant to various individuals in diverse contexts; describing as 'cosmographic' ideas and practices that were not considered as such by those who originated them only makes that task harder. Indeed, such 'contamination' of the historical record has contributed to cosmography being so poorly understood until very recently.