While Menion was a Crown Prince, during the Third War of the Races, a council in Culhaven sent him, Allanon, Balinor Buckhannah, Hendel, Shea Ohmsford and 2 Elves on the quest to find the Sword of Shannara.
He went to Kern and warned the town that Brona's armies were coming. He rescued Shirl Ravenlock from her kidnappers as the enemies burned the city. They came to Tyrsis and Menion warned Prince Palance Buckhannah that the army that burned Kern also marched toward Tyrsis. In the middle of the night he caught Stenmin trying to assassinate him. Menion forced Stenmin to lead him to Prince Balinor Buckhannah who was falsely imprisoned as a traitor. Menion freed him, and recognized Stenmin as one of Shirl's kidnappers. Stenmin escaped killing Palance Buckhannah on his way.
When Brona's army attacked the city, he with Hendel raced to block the enemies who were attepting to sneak into the city through secret passages, led by Stenmin. They fought their way to the cellar and Hendel fought bravely while Menion used all his strength to close the massive stone trapdoor. Suddenly Hendel called his name; he looked up and saw Hendel fall; he wept and then looked up at Stenmin who tried to sneak out of the cellar. Menion grabbed Hendel's mace and slew Stenmin. Then he went out to defend the Bridge of Sendic against the Trolls who had broken the gates.
He became the father of Shella Leah and a son. He trained her as a scout and tracker and gave her a locket, telling her to never to lose it. He like to tell her many stories and the two travelled to Tyrsis and visited the cellar.
Some 20 years after the War, while Shella was out hunting, Menion's gardener Ernst was replaced by the Shifter. Ernst sabotaged the garden, and while Winston like every evening served himsassafra tea from his garden, Menion was poisoned and fell ill. Jonas the herbalist prepared a mixture to aid his breathing but could not find the cause. Shella returned two days later with Jak Ohmsford and they quickly prepared an antidote after determining that Menion was poisoned by dreaddire.
The next day, Menion was visited by Allanon who warned him that Brona had returned. Shella wanted to join Jak on his quest, but worrying for her, Menion forbid her to go and ordered the gates of Leah shut.