This work is the true account of John Newton's life experiences relating to the African Slave Trade. He begins with a description of the current stance on slavery and the widespread push for abolishing it completely. He then details his personal experience as a slave to a vicious slave trader and his subsequent entrance into the business of slave trading. The bulk of his account is his retelling of the horrors he witnessed on board multiple slave ships. Newton also explains that at the time, he thought nothing of the atrocities he witnessed, and only after he became a minister did he realize the sins he had committed. Newton is sharing these personal experiences in this account in the hopes of making people join the movement to abolish slavery completely.
John Newton provides a more holistic view of the African Slave Trade and the effects it has, not only on the English, but on the slaves as well. He details the circumstances of the slave trade and how the real savages are not the natives, but the "civilized" English, because of the atrocities they commit against their fellow humans. The ideas Newton presents in this work are ahead of their time.
Most of Newton's, "Thought Upon the African Slave Trade" centers around his experiences on slave ships. The video below describes some of the artifacts recently recovered from an ancient slave ship, which may give you an idea of what the ships were like for the unfortunate slaves they carried.