Marth is a character in Nintendo's Fire Emblem series. He was the main character of the first, third, and eleventh Fire Emblem games, as well as being in many Super Smash Bros. games, beginning with Super Smash Bros. Melee. He was also the first DLC revealed for the latest Fire Emblem installment on the 3DS.
Marth was the son of King Cornelius of Altea and the younger brother of Princess Ellis. However, when Altea was invaded by a neighboring country, Doula, his father was killed and his sister was taken hostage. He was then exiled to the island kingdom of Talis. Two years later, Talis was overrun by pirates. The princess and Marth's longtime friend, Sheeda, seeked Marth and his army for help. He agreed, and after they sent the pirates packing, he went on a quest to win back Altea. In the end, he obtained the Fire Emblem and the Falchion sword, both of which were weld by Marth's ancestor Anri, defeated the Dark Sage Garnef as well as the Dark Dragon Medius, rescued Ellis, and liberated his kingdom.
Five years later, an ally of Marth's, Hardain, betrayed him by taking over and ruling the entire continent of Akaneia with an iron fist. He then gathered up his remaining allies and set off to defeat Hardain. When he did, Hardain revealed that he was possessed by Medeus, who was still alive. Afterwards, he got back the Fire Emblem and Falchion, and defeated Medeus again. This time for good. Afterwards, Marth, now king of Altea, married Sheeda and restored Akaneia to it's former glory.