Amanieu was made a
cardinal deacon in the
consistory of 20 March 1500 by
Pope Alexander VI. The pope sent him the
red hat on 2 October 1500 and he received the
deaconry of
San Nicola in Carcere on 5 October 1500. From 4 May to 10 October 1500, Amanieu was administrator of the
see of Oloron. He was administrator of the
see of Pamiers from 14 March 1502 until 1506. After Cardinal
Giuliano della Rovere sought refuge in
Savona, Amanieu was secretly despatched on 21 June 1502 to bring him back, but failed in this mission. Amanieu participated in both the
papal conclave of September 1503 that elected
Pope Pius III, and the
papal conclave of October 1503 that elected
Pope Julius II. After this second conclave he had to leave
Rome. Amanieu was administrator of the
see of Vannes from 8 January to 14 October 1504; of the
see of Bazas from 4 December 1504 until his death; of the
see of Lescar from 6 October 1507 until 20 June 1515; and of the
see of Pamplona from 13 May 1510 until 1512, and again from 1517 until his death. Amanieu participated in the plot of cardinals against Pope Julius II. In 1511, he attended the schismatic Council of
Pisa even after the pope threatened him with
excommunication. There, he was a strong supporter of the French party. After the death of Julius II, he did not participate in the
papal conclave of 1513 that elected
Pope Leo X. The new pope absolved Cardinal d'Albret (along with Cardinals
Guillaume Briçonnet and
René de Prie) and confirmed him in his offices. He also served as administrator of the
see of Pamiers from 1514 until his death. He became the
cardinal protodeacon on 3 September 1520. He died in
Casteljaloux on 20 December 1520. He is buried in Casteljaloux. ==Notes==