Why was the three-fifths compromise necessary?

The Three-Fifths Compromise defined the process for states to allow them to count slaves as part of the population to establish representation and taxation for the federal government.

Explanation:

The Southern states wanted to count all slaves toward the population for representation purposes but did not want to be taxed because of the slaves as the Southern states considered them property.

However, the Northern states did not want all the slaves to be counted  toward the population because that would take representation away from the North.  

saint clair’s defeat, (november 4, 1791), one of the worst defeats ever suffered by u.s. forces in indian warfare, precipitated by british-indian confrontation with settlers and militia in the northwest territory following the american revolution. despite specific provisions in the treaty of 1783 for the evacuation of its forts on the northwestern border, britain had failed to yield these lucrative fur-trading posts. in hopes of reclaiming lost hunting grounds with british support, a northwest indian confederation was gradually molded between 1785 and 1787, consisting mainly of shawnee, delaware, ottawa, iroquois, ojibwa, miami, and potawatomi. kentucky frontiersmen reacted to this threat by initiating raiding parties on native villages as early as 1788, and indian warfare flared up the following year.

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