Complex sentence: When King Lycurgus of Thrace heard that Dionysus was in his kingdom, he imprisoned all the followers (Maenads) of Dionysus; the god fled, taking refuge with Thetis, and sent a drought which stirred the people into revolt.
Split into simpler sentences: When King Lycurgus of Thrace heard that Dionysus was in his kingdom, he imprisoned Dionysus' followers, the Maenads. Dionysus fled and took refuge with Thetis, and sent a drought which stirred the people into revolt.