The environment of the New England colonies did not affect the development of slavery in this region. It did not affect the development of slavery because New England soil was not good for farming. Most slaves were used for farming, but since nobody owned a farm in this region, there was little need for slaves, period. Most of the New England region was industries and since the slaves would have to be taught how to do the job, the factory owners pretty much saw no purpose in even using slaves. Don't get me wrong, there may have been some parts of this region that WAS used for farming, but if there were any, it wasn't an abundant amount of them.
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