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MCDOUGAL LITTELL
2
World History: Patterns of Interaction
Critical Thinking: Analyzing
Causes and Recognizing Effects
Environmental Factors Shape River Valley Civilizations
© McDougal Littell Inc. All rights reserved.
CAUSE
EFFECT
People would settle in areas
with water and fertile soil for
farming.
The earliest civilizations
formed in river valleys.
Sumerian villages were located
on open plains without natural
barriers.
The Sumerians built fortified
cities to help villages protect
themselves.
The Nile River flowed through
upper and lower Egypt.
The Nile River helped unify
upper and lower Egypt by
creating a transport link.
China’s land forms featured
mountains and deserts.
Mountains and deserts were
barriers to invasion, which led
to an enduring Chinese culture.
The Indus River linked its
civilization to the sea.
Trade developed between the
Indus River civilization and
outside cultures.