Thus passed a two years' imprisonment, after which the Emperor deigned to offer terms to his captive. In the first place he required that Rupert should embrace the Roman faith. But the boy was a Palatine, and, though he had listened willingly to the persuasions of his aunt, Henrietta, the least hint of compulsion rendered him staunchly Protestant. He answered the Emperor, somewhat grandiloquently, "that he had not learnt to sacrifice his religion to his interest, and he would rather breathe his last in prison, than go out through the gates of Apostacy." The Emperor then consented to waive the question of religion, only insisting that Rupert must ask pardon for his crime of rebellion against the Holy Roman Empire. But to do this would have been to deny his brother's right to his Electorate, and Rupert only retorted coldly that he "disdained" to ask pardon for doing his duty. Finally, he was invited to take service under the Emperor, and to fight against France, which country had just imprisoned his eldest brother. But here also the boy was obdurate. To fight under the Emperor would inevitably involve fighting against the Swedes and the Protestant princes. Rupert therefore replied, "that he received the proposal rather as an affront than as a favour, and that he would never take arms against the champions of his father's cause."[23] After such contumacy it may well be believed that the Emperor's patience was exhausted. His brother-in-law the Duke of Bavaria, then owner of the Upper Palatinate, and of the ducal title which was Rupert's birthright, suggested that the boy's spirit was not yet broken, and urged the Emperor to deprive him of his privileges. Accordingly, Graf {46} Kuffstein was ordered to cease his civilities, and Rupert was placed in a confinement rendered stricter than ever, guarded day and night by twelve musketeers. For this severity the proximity of a Swedish army was an additional reason. Maurice himself was serving in their ranks, and the Emperor feared lest Rupert should hold correspondence with them. Against these Swedes was despatched the Emperor's brother, the Archduke Leopold, who, very happily for Rupert, passed, on his way, through Linz. Being at Linz, the Archduke naturally visited the youthful prisoner who had made so much sensation, and was forthwith captivated by him. Leopold, whose gentle piety had won him the name of "the Angel", was but a few years older than the Palatine; the two had many tastes in common, and in that visit was established a friendship between Rupert the Devil and Leopold the Angel, which endured to the end of their lives.