Complex sentence: Shortly afterward Henson was ordered on a trip south to New Orleans, and when he learned that he was to be sold there he obtained a weapon and contemplated murdering his white companions, but decided against violence because his Christian morals forbade it.
Split into simpler sentences: Shortly afterward Henson was ordered on a trip south to New Orleans. He contemplated murdering his white companions with the weapon, but decided against violence because his Christian morals forbade it.