Poets and artists from ancient times to the present have derived inspiration from Greek mythology and have discovered contemporary significance. Greek mythology is known today primarily from Greek literature and representations on visual media dating from the Geometric period from 900–800 BC onward. In fact, literary and archaeological sources integrate, Greek mythology has had an extensive influence on the culture, arts, and literature of Western civilization and remains part of Western heritage and language. Modern scholars refer to and study the myths in an attempt to throw light on the religious and political institutions of Ancient Greece and its civilization, and to gain understanding of the nature of myth-making itself. Geometric designs on pottery of the eighth century BC depict scenes from the Trojan cycle, as well as the adventures of Heracles. The discovery of the Mycenaean civilization by the German amateur archaeologist Heinrich Schliemann in the nineteenth century, and the discovery of the Minoan civilization in Crete by the British archaeologist Sir Arthur Evans in the twentieth century, helped to explain many existing questions about Homer’s epics and provided archaeological evidence for many of the mythological details about gods and heroes.