Masamune is an impulsive leader who is boldly arrogant of his abilities, believing himself to be superior to everyone around him. He deems others to be incompetent and often flings the line "Idiots!" or "Imbeciles!" to friend and foe alike. An independent thinker, he rarely listens to his vassals' advice and marches to his own rhythm. Though labeled as an upstart by his enemies, he is actually quite clever and is capable of turning the tides of the battle with his plots. He desires to explore the world and make a new society where numbers can rule. He values his wits, personal material wealth, and power, easily crushed when someone else surpasses him in these aspects. He is willing to bow down to others if it means keeping his ambitions alive. Masamune regrets missing his chance to become the land's unifier though he places importance on his survival as his means of respecting the dead.

Though he puts up a tough front, Masamune appreciates it when people praise him. His way of showing it, however, isn't exactly conventional as he may respond by yelling an insult to his listener or treating them coldly. He is good friends with Magoichi: both believe that their firearms are the weapons of the future and share a love for money. He regards Kojūrō as his living shadow. The young lord has never thought about life without him, and Masamune is considerably shocked by the danger of losing him. They may not always agree with one another yet the Date lord never doubts his retainer's boundless loyalty to him.

Due to their contrasting beliefs, he shares mutually antagonizing ties with Kanetsugu. Masamune bluntly deems him to be a hypocrite who uses morals as an excuse to lead men into war. He isn't a fan of Kanetsugu's self-righteous nature and can't stand his preachings for very long.

(Source: Koei Wikia)