two years old, or of entering the Order of Santa Clara in a Portuguese house. She chose the latter, but she never ceased to sign herself _Yo la Reina_, and her pretensions were a frequent source of anxiety. She led a varied life, sometimes treated as queen, with a court around her, and sometimes as a nun in her convent, dying at last in 1531, at the age of seventy.[53] Isabella was queen in fact as well as in name. Under the feudal system, the husband of an heiress was so completely lord of the fief that, in the Capitulations of Cervera, January 7, 1469, which preceded the marriage, the Castilians carefully guarded the autonomy of their kingdom and Ferdinand swore to observe the conditions.[54] Yet, on the death of Henry IV, he imagined that he could disregard the compact, alleging that the crown of Castile passed to the nearest male descendant, and that through his grandfather, Ferdinand of Antequera, brother of Henry III, he was the lawful heir. The position was, however, too doubtful and complicated for him to insist on this; a short struggle convinced his consummate prudence that it was wisdom to yield, and Isabella's wifely tact facilitated submission. It was agreed that their two names should appear on all papers, both their heads on all coins, and that there should be a single seal with the arms of Castile and Aragon. Thereafter they acted in concert which was rarely disturbed. The strong individuality which characterized both conduced to harmony, for neither of them allowed courtiers to gain undue influence. As Pulgar says "The favorite of the king is the queen, the favorite of the queen is the king."[55] [Sidenote: _FERDINAND'S CHARACTER_]