He was born at Guadalajara in New Castile, the chief lordship of his family, on the 3rd of May 1428. The house of Mendoza claimed to descend from the lords of Llodio in Alava, and to have been settled in Old Castile, in the 11th century. One chief of the house had been greatly distinguished at the battle of Las Navas de Tolosa in 1212. Another had been Admiral of Castile in the reign of Alphonso the Wise. Peter the Cruel had endowed them with the lordships of Hita and Buitrago. The greatness of the Mendozas was completed by Pedro Gonzalez, who sacrificed his life to save King John I at the battle of Aljubarrota in 1385. The cardinal's father, the marquis of Santillana-- to use the title he bore for the greater part of his life--was a poet, and was conspicuous during the troubled reign of John II.
Loyalty to the Crown was the traditional and prevailing policy of the family. Pedro Gonzalez, the future cardinal, was sent into the Church mainly because he was a younger son and that he might be handsomely provided for. He had no vocation, and was an example of the worldly, political and martial prelates of the 15th century. In 1452 at the age of twenty-four, he was chosen by the king John II to be bishop of Calahorra, but did not receive the pope's bull till 1454. As bishop of Calahorra he was also señor, or civil and military ruler, of the town and its dependent district. In his secular capacity he led the levies of Calahorra in the civil wars of the reign of Henry IV. He fought for the king at the second battle of Olmedo on August 20, 1467, and was wounded in the arm.
During these years he became attached to Doña Mencia de Lemus, a Portuguese lady-in-waiting of the queen. She bore him two sons, Rodrigo, who was once selected to be the husband of Lucrezia Borgia, and Diego, who was the grandfather of the princess of Eboli of the reign of Philip II (see Antonio Perez) By another lady of a Valladolid family he had a third son who afterwards emigrated to France. In 1468 he became bishop of Siguenza. In 1473 he was created cardinal, was promoted to the archbishopric of Seville and named chancellor of Castile. During the last years of the reign of King Henry IV. he was the partisan of the Princess Isabella, afterwards queen. He fought for her at the battle of Toro on March 1, 1476; had a prominent part in placing her on the throne; and served her indefatigably in her efforts to suppress the disorderly nobles of Castile. In 1482 he became archbishop of Toledo.
During the conquest of Granada he contributed largely to the maintenance of the army. On January 2, 1492 he occupied the town in the name of the Catholic sovereigns. Though his life was worldly, and though he was more soldier and statesman than priest, the "Great Cardinal," as he was commonly called, did not neglect his duty as a bishop. He used his influence with the queen and also at Rome to arrange a settlement of the disputes between the Spanish sovereigns and the papacy. Though he maintained a splendid household as archbishop of Toledo, and, provided handsomely for his children, he devoted part of his revenue to charity, and with part he endowed the college of Santa Cruz at Valladolid. His health broke down at the close of 1493. Queen Isabella visited and nursed him on his deathbed in Guadalajara. It is said that he recommended her to choose as his successor the Franciscan Jimenez de Cisneros, a man who had no likeness to himself save in political faculty and devotion to the authority of the Crown.
The life of the cardinal, by Salazar de Mendoza, Cronica del gran cardinal Don Pedro Gonzalez de Mendoza (Toledo, 1625), is discursive and garrulous but valuable. See also Prescott, History of Ferdinand and Isabella.
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