ɐlfˈɑːnsoʊ hɐdbɪn bᵻtɹˈoʊðd tə mˈæɹiə də kæstˈɪlə wˈʌn θˈaʊzənd fˈoːɹhˈʌndɹɪd wˈʌn wˈʌn θˈaʊzənd fˈoːɹhˈʌndɹɪd fˈɪfti ˈeɪt; sˈɪstɚɹ ʌv hwˈɑːn ɹˌoʊmən tˈuː ʌv kˈæstaɪl ɪn vˈælɐdˌɑːlɪd ɪn wˈʌn θˈaʊzənd fˈoːɹhˈʌndɹɪd ˈeɪt; ðə mˈæɹɪdʒ wʌz sˈɛləbɹˌeɪɾᵻd ɪn vɐlˈɛnʃiə dˈʊɹɹɪŋ wˈʌn θˈaʊzənd fˈoːɹhˈʌndɹɪd fˈɪftiːn.
Alfonso had been betrothed to María de Castilla (1401–1458; sister of Juan II of Castile) in Valladolid in 1408; the marriage was celebrated in Valencia during 1415.