New England states abolished slavery via the practice of gradual emancipation following the American Revolution

True.

Explanation:

It is true that following the American Revolution, abolishing of slavery was a gradual emancipation in New England. Most of the states abolished slavery in later half of the eighteen century.

Some Northern states abolished slavery following the American Revolution but some states like Connecticut and Rhode Island abolished slavery in the 1840s.

Therefore, the given statement is true.

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