The Trojans were involved in the Trojan War, they fought against many of the armies of Greece but eventually lost when they pushed a giant wooden horse, namely the Trojan Horse, secretly filled with Greek soldiers, into the middle of Troy. The Greeks came out in the middle of the night, opened the gates, and destroyed the city. Paris was the prince of Troy, he killed Achilles by shooting a poison arrow into his vulnerable heel.
In the God of War series
The Trojans appear in God of War: Ascension's multiplayer, they fight against the Spartans in order to gain the favour of the gods. It does not effect the warriors' stats if they are Trojan or Spartan. The Walls of Troy is a featured map, Trojans aim to destroy the Trojan Horse, while the Spartans target the Trojan's Statue of Apollo.