Final answer:
The northern camps that housed runaway slaves were known as "contraband camps" because the slaves seeking refuge there were seen as confiscated property and considered "contraband of war."
Step-by-step explanation:
The northern camps that housed runaway slaves were known as "contraband camps" because they were staffed by people who were legally seen as confiscated property. The term "contraband" was used to describe these individuals because they were considered to be property of the Confederacy that had been used to support the war effort. By escaping and seeking refuge in these camps, the slaves effectively became "contraband of war."
Learn more about Northern camps for runaway slaves