How were African American slaves coerced into slavery?

African tribes engaged in warfare and regularly took slaves from the tribes they defeated in battle. This was a standard procedure in the ancient world, and it continued in some areas until relatively late in human history. Turning defeated enemies into slaves did not mean turning whole tribes into slaves, but it did mean that captured enemies were considered slaves. As the profits from the slave trade increased, some tribes increased their raids on other tribes in order to capture more slaves for sale.
Slaves were subjected to horrible conditions during the Middle Passage. Those that survived were likely suffering from trauma and in shock by the time they went up for sale. After being sold, slaves were subjected to physical abuse and isolation from other groups. This, combined with the new surroundings, made it difficult for slaves to regain their previous identities and likely caused some depersonalization and other symptoms of severe trauma that may have looked like merely giving up.