Research Notes:

Her parentage and first marriage are confirmed by a testament of Armengol [IV] Comte de Urgell, cited by Monfar, under which the testator bequeathes his county "al infante don Pedro su sobrino hijo del rey d´Aragon" if his own son and brothers died. The date of her marriage suggests that she must have been born from her father´s first marriage, but this has not yet been corroborated by any primary source. Her second marriage is indicated by a document addressed by "comes Ermengaudus" to the comte de Cerdanya under which he promises that if he dies childless his property would be inherited by "germanam meam Elisabet coniugem tuam". In citing this document, Monfar misinterprets it as indicating that Isabel was the daughter of Comte Armengol [IV] and that her husband was "Guillen Jordan, penultimo conde de Cerdanya, que murio en el año 1102". Chronology dictates that this must be incorrect. “Willelmus Ceritanensis...comes” donated property to Cuxà, for the soul of “quondam uxoris meæ Elizabeth”, by charter dated 20 Dec 1071. No primary source has been identified which confirms conclusively that the first wife of King Sancho of Aragon was the same daughter of Comte Armengol [III] as the wife of Comte Guillem Ramon de Cerdanya. Nevertheless, this co-identity provides the best explanation of the documents cited, on the basis of the following argument. Firstly, the undated document (quoted above), under which Comte Armengol [IV] promised his county to his sister Isabel if he died childless, must be dated to before 20 Dec 1071 when Isabel is recorded as deceased. Secondly, Pedro, son of Sancho I King of Aragon by his first wife, issued charters in his own name in 1086, which indicates that he had reached the age of majority and therefore places his birth to before 1070 at the latest and so probably before the issue of that undated document (another source enables the dating of his birth more precisely to [1068/69]). Thirdly, it is most likely that King Sancho (of obviously superior rank to Comte Guillem Ramon) would have married the oldest sister of Comte Armengol [IV]. Fourthly, if that is correct, the wife of Comte Guillem Ramon (if a separate person) would have been a younger sister, junior in rank to any descendants of her older sister the wife of King Sancho, and therefore an unlikely choice as successor to Urgell if Pedro de Aragón was already alive. Fifthly, Pedro´s suitability as a candidate to succeed to Urgell is demonstrated by Comte Armengol [IV]´s testament which names him as fallback choice if the testator´s son and brothers all predeceased him. If the co-identity is correct, Isabel´s first marriage must have been annulled or she and her first husband otherwise separated but the circumstances of, or justification for, this annulment/separation are not known. ¹