In the book Guns, Germs, and Steel: The Fates of Human Societies by Jared Diamond, the author explains that environmental factors rather that inherent genetic differences are responsible for the rapid development and expansion of some societies, particularly those of Eurasia, rather than others. Due to its ambitious premise, the overall setting of the book is the whole world. In explaining his ideas, Diamond compares the geography, flora, and fauna of entire continents. However, he uses examples of particular places to illustrate his principles, so I'll highlight some of the most important of these settings.

The first important regional setting is in the prologue, called "Yali's Question." It takes place in New Guinea, and it explains the genesis of the ideas that caused Diamond to research and write Guns, Germs, and Steel. Diamond is taking a walk with a local politician named Yali, and Yali asks him:

Why is it that you white people developed so much cargo and brought it to New Guinea, but we black people had little cargo of our own?

By "cargo," Yali means manufactured goods and other items that the New Guineans had never developed. Diamond goes on to explain that for the next 25 years he attempted to answer that question.

In chapter 1, Diamond traces early human evolution across all the continents. In chapter 2, he focuses on the setting of the Pacific Ocean and the Polynesian Islands to show how that particular environment affected the exploration and expansion of the early islanders. In chapter 3, the setting is the Inca Empire in South America. Diamond describes how the Spanish, with just a small band of conquistadors, managed to conquer the overwhelmingly larger army of Atahualpa, the Inca emperor.

When writing about hunter-gatherers developing agriculture and settling into towns and cities, Diamond uses the setting of the Fertile Crescent in the Middle East as an example. He compares its abundance of plants suitable for agriculture and animals suitable for domestication with other parts of the world that had less ideal circumstances for settling into societies and the development of technology. He also compares the east-west axis of the Eurasian continent, which he considers ideal for trade and expansion, with the north-south axes of the Americas and Africa.

In part 4, "Around the World in Five Chapters," Diamond uses numerous settings to illustrate the ideas he has expressed earlier in the book. These setting include Australia and New Guinea, China and the rest of East Asia, Polynesia, Eurasia as compared with the Americas, and Africa.