Complex sentence: On April 29,1878, a posse including the Jesse Evans Gang and the Seven Rivers Warriors, under the direction of Sheriff Peppin, engaged Regulators McNab, Ab Saunders, and Frank Coe in a shootout at the Fritz Ranch.
Split into simpler sentences: On April 29,1878, Sheriff Peppin was directing a posse that included the Jesse Evans Gang and the Seven Rivers Warriors. They engaged in a shootout with the Regulators McNab, Saunders, and Frank Coe at the Fritz Ranch.