Slavery in the American colonies was?

concentrated mostly in the New England colonies.

concentrated mostly in the middle colonies.

concentrated mostly in the southern colonies.

evenly distributed throughout all the colonies.

Well I would say that slavery was in the American colonies was concentrated mostly in the southern colonies. because the southern colonies were agricultural based, and they relied on slaves to work the plantations.

Concentrated mostly in the southern colonies.

Explanation:

Slavery was mostly concentrated in the Southern Colonies, especially because of the cotton plantations. Slavery was a part of the success of the cotton plantations in the south, especially after the invention of the cotton gin.