The Origins of the Modern World: A Global and Ecological Narrative from the Fifteenth to the Twenty-first Century

Marks considers the environmental and economic state of the world by the year 1400. Today, the human population exceeds eight billion, but in 1400 it was only 380 million. Almost all people lived in rural areas, and human settlements covered 7% of the land on Earth. Although the world has many more people today, 70% of them live on the same 7% of land or 4.25 million square miles as their ancestors in 1400. In addition, Marks identifies 15 advanced civilizations. These civilizations were the ultimate product of an “agricultural revolution” that began in modern-day Iraq when people transitioned from hunting-and-gathering to permanent agricultural settlements. The settlements gave rise to social hierarchies, in which most of the population made food through agriculture and an elite of priests and rulers needed to explain and protect society. The settlements also gave rise to artisans, who made and maintained the items necessary for society and culture, and to trade between cities and tribes.

Even by 1400, the world’s largest urban populations amounted to only 1% of the global population. Nine of the world’s largest cities were in China, and the biggest was Nanjing. The second largest city was Vijayanagar in southern India, and the third was Cairo in Egypt. Another 9% of the global population lived in smaller cities and towns. Urban areas depended on the taxes and other payments made by peasants. Also, the movement of food from farms to cities led to “metabolic rift,” meaning the decline of nutrients in the soil, which often had negative consequences for farming. Outside the best agricultural territories were the great steppes of Central Asia. These areas were predominantly inhabited by nomads, who depended on herds of sheep, goats, cattle, and horses and traded with towns and cities for salt, textiles, and manufactured products like cookery. The nomads did not live in settlements, but they raided and even invaded and conquered settled societies in times when those societies became weaker. Other groups outside settled civilization lived in environments not conducive to agriculture, like swamps, forests, and mountains, but were self-sufficient.

Humans had to coexist with wildlife more than they do today. Wolves were common in most of Europe and even invade towns and cities at times when populations declined or food was rare. In most of China, tigers posed a common threat to villages. Wildlife was most plentiful in Africa and the Americas. In Africa, populations of larger animals survived better than elsewhere since these animals “evolved with humans” (27). In the Americas, animal populations expanded massively after Indigenous American populations declined due to European diseases.

In the 15th century, human population growth could happen only from agriculturally cultivating more land, “increasing the labor inputs on a given plot of land” (29), or increasing fertilizer or water. Famine was common. It resulted not just from natural causes like drought but because in most of Eurasia, “peasant families gave up as much as half of their harvest to the state and landlords as taxes and rents” (30). This increased pressure on the agricultural output of peasants contributed to famine. Therefore, Marks argues that famine should be understood as a “social” rather than “natural” occurrence. However, peasants also had “concepts of their own about what rights they had in society, and under what conditions they could press them” (30). As a result, societies from the time of 1400 was not exclusively run by the ruling elites but through negotiations and agreements among peasants, landowners, and states.

Another factor that shaped life around 1400 was the “biological old regime” (31), specifically energy and nutrients. People needed plants for food, heating fuel, and making products. Although windmills and water wheels were available in some places, most work was performed by humans or animals like horses and donkeys. This required humans and animals to get energy from nitrogen, which is consumed through food. The process by which nitrogen returns to the environment, the “nitrogen cycle,” limited the amount of food that could be produced through farming. However, the invention of synthetic nitrogen fertilizer in the 20th century removed this limit on agricultural production and led to the human population growing from 1.6 to 7 billion in just the 1900s.

In 1400, eight “trading zones” linked Europe, Asia, and Africa. Three main trade routes existed: a northern route through the Black Sea to China, a central route through Baghdad and the Persian Gulf to East Asia, and a southern route from Cairo to the Red Sea and the Indian Ocean. Marks argues that this world system of trade was “polycentric”, meaning that each trade region equally had a wealthy “core” and a “periphery” that supplied agricultural and manufactured goods for trade. This changed by 1800, when European colonization created a more unequal, global system “with a highly developed core and an underdeveloped periphery” (36). Marks suggests that understanding that by 1400 trade was more interconnected than previous historians thought helps explain the spread of the Black Death (or the plague), which was caused by the bacteria Yersinia pestis and spread by black rats and fleas. Although the Black Death devastated populations from East Asia to Europe, it created more land and resources for survivors.