House of Trastámara (1479–1555)

Under Isabella and Ferdinand, the royal dynasties of Aragon and Castile were united into a single line. Historiography of Spain generally treats this as the formation of the Kingdom of Spain, but in actuality, the two kingdoms continued for many centuries with their own separate institutions. It wasn't until the Nueva Planta decrees of the early 18th century that the two lands were formally merged into a single state.

NameLifespanReign startReign endNotesFamilyImage
Ferdinand V of Castile, (II of Aragon)

the Catholic

10 March 1452 – 23 January 1516
(aged 63)
15 January 1475
Castile
20 January 1479
Aragon
26 November 1504
Castile
23 January 1516
Aragon
Son of John II of Aragon and Juana Enríquez Trastámara Ferdinand II of Aragon
Isabella I

the Catholic

Spanish spelling: Isabel I

22 April 1451 – 26 November 1504
(aged 53)
11 December 1474
Castile
26 November 1504
Castile
Daughter of John II of Castile and Isabella of Portugal Trastámara Isabella of Castile
Joanna of Castile

the Mad

Spanish spelling: Juana I

6 November 1479 – 12 April 1555
(aged 75)
26 November 1504
Castile
23 January 1516
Aragon
12 April 1555 Daughter of Isabella I of Castile and Ferdinand II of Aragon Trastámara Joanna I
Philip I

the Handsome

Spanish spelling: Felipe I

22 July 1478 – 25 September 1506
(aged 28)
27 June 1506
Castile
25 September 1506
Castile
Husband of Joanna of Castile Habsburg  Philip I