Complex sentence: Darius I of Persia divided the largest Anatolian state of that time, Cappadocia, into two, with Zela remaining in Pontus Cappadocia, the northern region.
Split into simpler sentences: Darius I of Persia divided the largest Anatolian state of that time, Cappadocia, into two. Zela remained in Pontus Cappadocia, the northern region.