How do historians compare the causes and effects of the major trade networks of the period?
Topic 2.7 Comparison of Economic Exchange: applying the historical reasoning skill of comparison to the causes and effects of the Silk Roads, Indian Ocean, and trans-Saharan networks.
A focused answer to AP World History Topic 2.7, the comparison reasoning skill applied to Unit 2: comparing the causes, goods, technologies, and effects of the Silk Roads, Indian Ocean, and trans-Saharan trade networks, and how to structure a comparison essay.
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What this topic is asking
Topic 2.7 is a reasoning-skill topic. The College Board is not introducing new content; it asks you to apply the historical reasoning skill of comparison to the trade networks of Unit 2. You should be able to compare the causes, goods, technologies, and effects of the Silk Roads, the Indian Ocean, and the trans-Saharan networks, and to explain the reasons for their similarities and differences in an essay.
What comparison means on the AP exam
The exam tests three reasoning skills: comparison, causation, and continuity and change. Topic 1.7 anchored comparison in Unit 1; Topic 2.7 anchors it again for the trade networks.
Comparing the three networks
Lay the networks side by side on shared points of comparison.
Similarities across all three:
- Each grew because of commercial and technological innovation (caravanserai and credit; the dhow, compass, and monsoon knowledge; the camel and caravans).
- Each spread religion, especially Islam, along its routes, plus ideas and technologies.
- Each created diasporic merchant communities and enriched the states that controlled them.
Differences in geography, transport, and goods:
- Silk Roads: overland by camel caravan; carried high-value luxuries (silk, porcelain) only; spread Buddhism and Islam; secured in this period by the Mongols.
- Indian Ocean: seaborne by dhow and junk, using the monsoon winds; could carry bulk goods as well as luxuries; built the Swahili city-states; spread Islam by sea.
- Trans-Saharan: across desert by camel caravan; centered on the gold-for-salt exchange; built West African empires such as Mali; spread Islam south.
Reasoning well: explaining the reasons for difference
A second mark of strong reasoning is recognizing that the networks were interconnected, not isolated: African gold reached the Indian Ocean via the Swahili coast, and goods passed between systems. They formed one Afro-Eurasian web.
Try this
Q1. Name the three historical reasoning skills tested on the AP exam. [Recall]
- Cue. Comparison, causation, and continuity and change over time.
Q2. Identify one similarity and one difference between the Silk Roads and the Indian Ocean network, and explain the difference. [Short explanation]
- Cue. Similarity: both grew from innovation and spread Islam. Difference: the Silk Roads carried only luxuries overland, while the Indian Ocean carried bulk goods by sea, because ships hold far more cargo than camels.
Exam-style practice questions
Practice questions written in the style of College Board exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
AP 2018 (style)6 marksCompare the causes and effects of two of the major trade networks (Silk Roads, Indian Ocean, trans-Saharan) in the period c. 1200 to c. 1450.Show worked answer →
A Long Essay Question (LEQ), scored on the 6-point comparison rubric.
Thesis (1): "Both the Silk Roads and the Indian Ocean network grew from commercial and technological innovation and spread religion and goods, but the Indian Ocean moved bulk goods by sea while the Silk Roads were limited to luxuries by land."
Contextualization (1): situate both within an Afro-Eurasia of rising states and growing demand.
Evidence (2): Silk Roads (caravanserai, luxuries such as silk, the spread of Buddhism); Indian Ocean (monsoon winds and dhows, bulk goods, the Swahili coast, the spread of Islam).
Comparison analysis (2): explain HOW they were similar (innovation drove growth; both spread religion) and different (overland luxuries versus seaborne bulk), then add complexity by noting that the networks were interconnected, not isolated.
AP 2021 (style)3 marksBriefly describe ONE similarity between two trade networks of this period. Briefly describe ONE difference. Briefly explain ONE reason for that difference.Show worked answer →
A Short Answer Question (SAQ) testing comparison directly, 3 points.
A. Similarity: both the trans-Saharan and Indian Ocean networks spread Islam along their routes through Muslim merchants.
B. Difference: the trans-Saharan trade crossed desert by camel caravan, while the Indian Ocean trade crossed water by ship using the monsoon winds.
C. Reason: the difference reflects geography and technology - the Sahara required the camel, while the ocean required ships and knowledge of the monsoons.
The skill is comparison: identify a similarity and a difference and explain why the difference existed.
Related dot points
- Topic 2.1 The Silk Roads: the causes and effects of the growth of the Silk Road trade network, including the commercial innovations and goods that flowed along it.
A focused answer to AP World History Topic 2.1, explaining how commercial innovations such as the caravanserai, money economies, and credit expanded the Silk Roads, the luxury goods and ideas that travelled them, and the diasporic merchant communities they created.
- Topic 2.2 The Mongol Empire and the Making of the Modern World: the rise and rule of the Mongol Empire and its effects on trade, technology transfer, and the connectivity of Eurasia.
A focused answer to AP World History Topic 2.2, explaining how the Mongols built the largest land empire in history, the Pax Mongolica that secured Eurasian trade, and the technology and cultural transfers their conquests accelerated across the continent.
- Topic 2.3 Exchange in the Indian Ocean: the causes and effects of the growth of Indian Ocean trade, including the technologies, goods, and diasporic communities it produced.
A focused answer to AP World History Topic 2.3, explaining how monsoon winds and maritime technologies such as the dhow, compass, and astrolabe drove Indian Ocean trade, the bulk and luxury goods it carried, the rise of the Swahili city-states, and its diasporic merchant communities.
- Topic 2.4 Trans-Saharan Trade Routes: the causes and effects of the growth of trans-Saharan trade, including the camel, the goods exchanged, and the empires it sustained.
A focused answer to AP World History Topic 2.4, explaining how the camel saddle and caravans, the gold-for-salt exchange, and Islamic commercial networks drove trans-Saharan trade, and how it built West African empires such as Mali.
- Topic 2.5 Cultural Consequences of Connectivity: the spread of religions, technologies, scientific and literary ideas, and the circulation of travellers across the trade networks.
A focused answer to AP World History Topic 2.5, explaining how the trade networks spread religions such as Islam and Buddhism, transferred technologies like paper and gunpowder, carried scientific and literary ideas, and circulated travellers such as Ibn Battuta and Marco Polo.
Sources & how we know this
- AP World History: Modern Course and Exam Description — College Board (2020)