The Trojan war:
The Trojan war is a war between the Greeks and the Trojans. The war lasted from 1194 to 1184 BC. The was had began when Sparta's Queen Helen was captured by the Trojan prince Paris. This angered Menelaus, the husband so he told is brother, the king of Mycenae to send a fleet of 1,000 ships in search of her.
Relation to the Odyssey:
In the odyssey a hero named Odysseus took 10 years to come back Ithaca. This was exactly how long the war was. The relation is that the Odyssey is after the Trojan war and is mythology.
Who is Homer:
Homer is a Greek epic poet. He is most know for his The Iliad and The Odyssey. He was born somewhere on the lines of 750 BC and 1200 BC. He might have been born in Asia Minor. There isn't that much know of this author.