Exploration of the new world was encouraged by a desire for direct trade routes by sea.
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Chicago became a transportation and commercial center in 1850's. The extraordinary growth of the city in the 1850's was attributed to the rapid increase of railroads namely the Galena & Chicago Union Railroad and their effects which made transportation and trading of goods easier than the previous method of trading by steamboats. Moreover the direction of trade shifted from north-south to east-west.
The settlements in Denver increased in 1858 due to the Pike's Peak Gold Rush.This was the first historical settlement in the city of Denver.
Most literature written during the Harlem Renaissance wanted to present the idea of the New Black Man who was sophisticated and educated.