• Born: Abt 1179
• Married (1): 1198
• Married (2): Feb 1210, Messina, Italy
• Died: 23 Jun 1222, Catania, Italy
• Buried: Palermo Cathedral, Sicily

  Research Notes:

The Gestis Comitum Barcinonensium names "Constantia" as oldest of the three daughters of "Ildefonsi", specifying that she married "Regi Ungariæ" but returned childless to Aragon after his death. The Chronicon Dubnicense records that "Emericus" married "Constancia filia regis Aragonie Cesari Friderico". The "Corónicas" Navarras name "al yfant don Pedro, rey d'Aragón, et al marqués de Provença don Alfonso, et a don Ferrando, abbat de Mont aragón, et una filla que casaron en Ongría" as the children of "el rey don Alfonso d'Aragón" and his wife. The Chronicle of Alberic de Trois-Fontaines names "Constantia regina" as wife of "Hemericus filius [regis Hungarie Bela]", specifying that she later married "Frederico imperatori". The Historia Sicula of Bartolomeo di Neocastro names "Constancia soror…Iacobi regis Aragonum" as the first wife of "dominus Fridericus secundus…Romanorum…imperator". The Continuatio Admuntensis records that she took her son to Vienna and, after his death, Leopold Duke of Austria arranged her repatriation to "fratri suo Hyspaniarum regi".

The Crónica de San Juan de la Peña records that Pedro II King of Aragon arranged the marriage of his sister Constanza to "Fredrico Rey de Sicilia". The Ryccardus de Sancti Germano Annales record the marriage in 1209 of "Fredericus rex Sicilie" and "Constantiam sororem regis Arragonum". The Continuatio Claustroneoburgensis records the marriage of "Fridericus rex Apulie" and "filiam regis Arragonis, relictam regis Ungarie".

Named Regent of Sicily by her husband in 1212, during his absence in Germany until 1220. She was crowned Empress at Rome with her husband 22 Nov 1220.

The monk Conrad´s Brevis Chronica records the death "apud Cataniam" in 1222 of "domina Constantia imperatrix…prima uxor Frederici imperatoris". ¹