Menelaus was the king of Mycenea or Sparta. His place in literature comes from his famous wife Helen of Troy. Helen considered to be the most beautiful woman in the world was pursued by many princes and Kings. The final decision as to who would be her husband came from drawing straws. Menelaus won.
Homer's Iliad tells the story of Paris, prince of Troy, who visits Menelaus at his palace. Paris has been promised by Aphrodite the most beautiful woman to marry. There he sees Helen and is smitten by her.
Thinking only of himself, Paris forgets the consequences of his actions and persuades Helen to come with him and be his lover. She accompanies him to Troy. The Trojans refuse to return Helen to Menelaus. From these events, a twenty year war encompasses most of Greece.
Of course, Menelaus is not happy. He calls on all of the rulers who had promised to help him if anyone tried to take Helen from him. Among these rulers, are Agamemnon, Menelaus's brother, and eventually the ruler of the Greeks, who lay seige on Troy to return Helen and gain revenge for this afront to Menelaus.
During the war, Menelaus played a minor role in the fighting, but he did face Paris in single combat. Although Menelaus came close to killing Paris, Aphrodite intervened and saved Paris, her personal favorite.
Rightfully, this should have ended the war. Paris had been defeated, and Helen should have been returned to her husband. Not so, in Greek mythology or in the Iliad.
After many years of fighting and scores of deaths, the Greeks create the Trojan horse. Menelaus was one of the Greeks hidden inside the belly of the horse. This ploy ended the Trojan war.
Menelaus was intent on killing Helen for her deception and rebuking her oath to him. Yet, when he saw her beauty, he wilted and took her back into his arms.