 During the first half of his reign Charles relied heavily on his uncle, Charles of Valois, for advice and to undertake key military tasks.Charles of Valois was a powerful magnate in his own right, a key advisor to Louis X, and he had made a bid for the regency in 1316, initially championing Louis X's daughter Joan, before finally switching sides and backing Philip V. Charles of Valois would have been aware that if Charles died without male heirs, he and his male heirs would have a good claim to the crown.Charles came to power following a troublesome two years in the south of France, where local nobles had resisted his elder brother Philip V's plans for fiscal reform, and where his brother had fallen fatally ill during his progress of the region.