Grumman

Grumman is a lean, elderly man with gray hair and a distinctive mustache, most often seen in his military uniform. He is also a nimble quick-change artist, able to slip convincingly into disguise, on one occasion dressing as an old woman to meet Mustang unnoticed.

On the surface Grumman is warm, jovial, and endlessly wry, a mentor and friend to Mustang who teases his subordinates like a doting uncle, at one point needling Roy to marry his granddaughter, who proves to be Riza Hawkeye. That genial front conceals a sharp, calculating, deeply ambitious mind. Disgusted by the government's corruption and unafraid of aging or death, he scoffs at the pursuit of immortality as something humans have no business chasing.

He prefers to work from the shadows and harbors real designs on power, aiming like Mustang for the office of Führer, though both want it to mend the country. Major Miles suspects he deliberately held Briggs troops back from the assault on Central so that Mustang and Olivier Armstrong would absorb the blame while he seized control, a reading that fits his careful moves. A hopeful realist, he is genuinely intrigued by the notion that humans and Homunculi might one day coexist. He also has an eccentric, mildly lecherous streak, fond of cross-dressing and known to grope Rebecca Catalina when she isn't paying attention.

Grumman enters the story playing chess with Mustang just as Roy's transfer to Central comes through, losing to him for the first time and handing over the board as a parting gift. He approves the reassignment of Mustang's subordinates, his granddaughter Riza among them. Later, as Mustang searches the military's upper ranks for allies, Grumman's contacts steer him toward General Raven, who turns out to be conspiring with the Homunculi, leaving Mustang open to blackmail. Once stripped of his subordinates, Mustang reaches Grumman secretly through Madame Christmas, using a note hidden inside the king piece of that chessboard, and the two meet in disguise at Maes Hughes' grave to trade intelligence and plot.

Grumman explains that Raven had once tried to recruit him into building an immortal army and, upon his refusal, buried him in the dead-end Eastern post. Unwilling to be branded a traitor and risk his rise, he backs Mustang and Armstrong only from behind the curtain, relaying word of the Promised Day, sending Rebecca Catalina to warn Riza, and blowing up the Führer's train while leaving the open fight to the younger officers. He falls to the Nationwide Transmutation Circle but is restored by Hohenheim's countermeasure. With Mustang blinded, Grumman is asked to take command of Amestris and gladly becomes Führer. Two years on he still holds the office, musing with Mrs. Bradley, whom he has let keep Selim, over whether humans and Homunculi can truly live together. In the 2003 anime his part ends soon after Roy's transfer, with only a few brief later cameos.