Answer:
It banned slavery in the territories acquired after the War with Mexico
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The American Revolution was precipitated, in part, by a series of laws passed between 1763 and 1775 that regulating trade and taxes. This legislation caused tensions between colonists and imperial officials, who made it clear that the British Parliament would not address American complaints that the new laws were onerous. British unwillingness to respond to American demands for change allowed colonists to argue that they were part of an increasingly corrupt and autocratic empire in which their traditional liberties were threatened. This position eventually served as the basis for the colonial Declaration of Independence<span>.</span>
Shi Huangdi
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African-Americans chose to fight for the British instead of the colonist plantation owners because they wanted to put their efforts in helping the British because if the British won the war the American-American citizens would be set free.