The Emancipation Proclamation freed slaves living in ten states that were still in rebellion. Slaves that were already in a state that was taken over before the EP were not freed. At the same time, all those freed slaves were enlisted in the Union Army. As a result, after some time black slaves and white citizens of the USA fought together against one enemy. No doubt, the Civil War united black and white people as well as reduced tensions existing among them. The majority of freed black slaves fought rather valiantly and earned the respect of whites. This promoted equality and eradicated some racial prejudices in the society.
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The lightbulb introduced cities to light and helped pave the way for offices to be lit and people to see at night and walk around
The Missouri river and the Columbia River were the two rivers they came across on their expedition,