24 November 1522,
Marshal Pedro de Navarra was killed in Valladolid in prison. He was the leader and important political figure of the Navarro army. He was arrested at Roncal in 1516, in the second attempt to recover the kingdom. Official sources said he committed suicide, but it is known that he was killed beheaded by order of Emperor Charles I, as the imprisoned Spanish community chief. Before, the emperor offered freedom to Marshal Peter in exchange for his service, but he refused.
Source:
Joseba Asiron and Martín Altzueta, 50 key dates of the conquest of Navarra (1512-1525). (Txalaparta).