He was the Son of that _Don Denis_, who was so successful in all his Undertakings, that it was said of him, that he was capable of performing whatever he design’d, (and of _Isabella_, a Princess of eminent Virtue) who when he came to inherit a flourishing and tranquil State, endeavour’d to establish Peace and Plenty in abundance in his Kingdom. And to advance this his Design, he agreed on a Marriage between his Son _Don Pedro_ (then about eight Years of Age) and _Bianca_, Daughter of _Don Pedro_, King of _Castile_; and whom the young Prince married when he arriv’d to his sixteenth Year. _Bianca_ brought nothing to _Coimbra_ but Infirmities and very few Charms. _Don Pedro_, who was full of Sweetness and Generosity, lived nevertheless very well with her; but those Distempers of the Princess degenerating into the Palsy, she made it her request to retire, and at her Intercession the Pope broke the Marriage, and the melancholy Princess conceal’d her Languishment in a solitary Retreat: And _Don Pedro_, for whom they had provided another Match, married _Constantia Manuel_, Daughter of _Don John Manuel_, a Prince of the Blood of _Castile_, and famous for the Enmity he had to his King. _Constantia_ was promised to the King of _Castile_; but the King not keeping his word, they made no Difficulty of bestowing her on a young Prince, who was one Day to reign over a number of fine Provinces. He was but five and twenty years of Age, and the Man of all _Spain_ that had the best Fashion and Grace: and with the most advantageous Qualities of the Body he possest those of the Soul, and shewed himself worthy in all things of the Crown that was destin’d for him. The Princess _Constantia_ had Beauty, Wit, and Generosity, in as great a measure as ’twas possible for a Woman to be possest with; her Merit alone ought to have attach’d _Don Pedro_, eternally to her; and certainly he had for her an Esteem, mix’d with so great a Respect, as might very well pass for Love with those that were not of a nice and curious Observation: but alas! his real Care was reserved for another Beauty. _Constantia_ brought into the World, the first Year after her Marriage, a Son, who was called _Don Louis_: but it scarce saw the Light, and dy’d almost as soon as born. The loss of this little Prince sensibly touched her, but the Coldness she observ’d in the Prince her Husband, went yet nearer her Heart; for she had given her self absolutely up to her Duty, and had made her Tenderness for him her only Concern: But puissant Glory, which ty’d her so entirely to the Interest of the Prince of _Portugal_, open’d her Eyes upon his Actions, where she observ’d nothing in his Caresses and Civilities that was natural, or could satisfy her delicate Heart.