Oguma

Ogma (Japanese: オグマ Oguma) is the leader of the mercenary warriors in the service of Talys. Originally a gladiator enslaved in Knorda's arena, he participated in a mass escape attempt, letting himself be captured so that everyone else, including Samto, could escape; he was to be disciplined but was found by Princess Caeda, who instead recruited him into the Talys army. He is deployed by King Mostyn as Caeda's personal guard when she leaves with Marth in the War of Shadows. Three years later, Mostyn dispatches him to Grust to assist Lorenz in protecting the country's royal children, Yubello and Yumina, from Archanean forces.

(Source: Fire Emblem Wiki)