Career
He was a descendent of Alonso Pérez de Guzmán. The Counts of Niebla, existed from no later than 8 June 1369 by the second marriage of Juan Alonso de Guzman y Cabrera, also named Juan Alonso de Guzman y Osorio (1342–1396), who was married twice, first to Juana Enriquez (d 1376), and then Beatriz de Castilla y Ponce de Leon (d 1409), an illegitimate daughter of Henry II of Castile.