When his brother , Filippo Emanuele , died in 1605 , he became heir - apparent to the Duchy of Savoy .
When his brother , Filippo Emanuele , died in 1605 , he received the homage of the court at Racconigi on 21 January 1607 .
When his brother , Filippo Emanuele , died in 1605 , he became heir - apparent to the Duchy of Savoy and received the homage of the court at Racconigi on 21 January 1607 .