 The British historian Denis Mack Smith wrote that it is not entirely clear why Victor Emmanuel was prepared to sacrifice his 10-year-old son's right to succeed to the throne in favor of the Duke of Aosta.Umberto was brought up in an authoritarian and militaristic household and expected to "show an exaggerated deference to his father"; both in private and public Umberto always had to get down on his knees and kiss his father's hand before being allowed to speak, even as an adult, and he was expected to stand to attention and salute whenever his father entered a room.Like the other Savoyard princes before him, Umberto received a military education that was notably short on politics; Savoyard monarchs customarily excluded politics from their heirs' education with the expectation that they would learn about the art of politics when they inherited the throne.