A primary source is about somebody that witnessed an event or something
A secondary source comes from someone that heard that didn’t witness the event
For example the news is a secondary source and the person that was at the event is primary
I would say to try william bayard
Lincoln Douglas made a point of telling how horrible slavery was in regard to the fact that he was not allowed to have any leisure time, he was often beaten, and was denied access to an education for some time.
The bataan death march is considered a war crime, because the prisoners were mistreated, they were not treated as humans, etc
hope this helps