I want to know the answer to the following question:
In what century was polygenism most widespread?
All the background I'm provided with is that "In the last two decades of the 18th century, the theory of polygenism, the belief that different races had evolved separately in each continent and shared no common ancestor, was advocated in England by historian Edward Long and anatomist Charles White, in Germany by ethnographers Christoph Meiners and Georg Forster, and in France by Julien-Joseph Virey.". Is that enough to answer the question?
Answer: no