The Trojan War was one of the most important wars in the history of Ancient Greece. It happened between the Trojans and the Greeks. It is mostly known through the "Iliad," an epic poem written by the Ancient Greek poet Homer.In the middle 19th century scholars thought Troy and the war were mythical; that they never existed. However, Heinrich Schliemann discovered the site of ancient Troy, across the Aegean Sea on Asia Minor. The war may have taken place in the 12th century BC.