quality:correction, structural:summarization, information:highlighting
Birth and family

Rodrigo de Borja was born in 1 January 1431, in the town of Xàtiva near Valencia, one of the component realms of the Crown of Aragon, in what is now Spain. He was named for his paternal grandfather, Rodrigo Gil de Borja y Fennolet. His parents were Jofré Llançol i Escrivà (died bef. 24 March 1437) and his Aragonese wife and distant cousin Isabel de Borja y Cavanilles (died 19 October 1468), daughter of Juan Domingo de Borja y Doncel. He had a younger brother, Pedro. His family name is written Llançol in Valencian and Lanzol in Castillian. Rodrigo adopted his mother's family name of Borja in 1455 following the elevation to the papacy of maternal uncle Alonso de Borja (Italianized to Alfonso Borgia) as Calixtus III. His cousin and Calixtus's nephew Luis de Milà y de Borja became a cardinal.

Gerard Noel writes that Rodrigo's father was Jofré de Borja y Escrivà, making Rodrigo a Borja from his mother and father's side. However, Cesare, Lucrezia and Jofre were known to be of Llançol paternal lineage. G. J. Meyer suggests that Rodrigo would have likely been uncle (from a shared female family member) to the children, and attributes the confusion to attempts to connect Rodrigo as the father of Giovanni (Juan), Cesare, Lucrezia, and Gioffre (Jofré in Valencian), who were surnamed Llançol i Borja.