Through multiple revolutions people have adapted to and affected their environments. As civilizations settled, new advances in agriculture and tools were made to allow for a less-nomadic society. Through advances such as iron tools and food stock, civilizations settled creating the basis for large empires to come later. Also through the innovation of weapons and armor, empires were able to better control and defend larger territory allowing for exponential expansion. Finally, with new advances made by different civilizations, trade increased as demand for new products from other empires grew.
The primary source document that could help a historian understand why the US Civil War started is a Charleston Mercury editorial published in 1860 because it contains factual accounts of the events during that time.
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