Complex sentence: They indicted Copperheads for criminal conspiracies to free Confederate prisoners of war, and played on the spirit of nationalism and the growing hatred of the slaveowners, as the guilty party in the war.
Split into simpler sentences: They indicted Copperheads for criminal conspiracies to free Confederate prisoners of war. They played on the spirit of nationalism and the growing hatred of the slaveowners, as the guilty party in the war.