King Pedro I 'the Cruel' of Castile (d. 1369)
Pedro I 'the Cruel' (1334 - 1369), king of Castile, son of king Alphonso XI of Castile and Maria of Portugal. Pedro was the last ruler of the main branch of the house of Burgundy; Constanza was his second daughter with Maria de Padilla.
For more information about the affairs of Spain and Portugal see P.E. Russell, The English Intervention in Spain and Portugal in the Time of Edward III & Richard II. Clarendon Press (Oxford, 1955); Id., "The War in Spain and Portugal", in Froissart: Historian, ed. J.J. N. Palmer, The Boydell Press - Rowman & Littlefield (Woodbridge, Suffolk - Totowa, NJ, 1981), pp. 83-100.
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