Pope Martin V
A moment of drastic change in policy was his marriage to the Latin noblewoman Cleofa Malatesta, arranged with the help of her uncle Pope Martin V, who became Theodore's ally and supporter. In a letter from around the time of Manuel II's death (July 21, 1425), Pope Martin V called Theodore II emperor of Constantinople ("ad Theodorum imperatorem constantinopolitanum") but the crown actually passed to his older brother John VIII.