St. Nuno Álvares Pereira (born June 24, 1360, Bonjardim, Portugal—died April 1, 1431, Lisbon; canonized April 26, 2009; feast day November 6) was an outstanding Portuguese military leader, known also as the Holy Constable, whose victory over Castilian forces in the historic Battle of Aljubarrota (August 14, 1385) ensured his nation’s independence.
Pereira distinguished himself in battle at age 13, fighting against the Castilians in their invasion of 1373. On the death of Ferdinand I of Portugal (October 1383), Pereira came forward as a supporter of João of Aviz (later John I, king of Portugal), the illegitimate son of Ferdinand’s father, Peter I, against the claims of Ferdinand’s daughter Beatriz, whose marriage to John I of Castile posed a threat to Portugal’s independence. In January 1384 John I invaded Portugal. Despite the fact that most of his family favoured Castile, Pereira continued to support João and defeated the Castilians in the Battle of Atoleiros (April 6, 1384). Further brilliant and heroic actions as a field commander won him the office of constable of the kingdom in 1385.
Although the Castilians had withdrawn in 1384, they invaded again the following year and moved on Lisbon. Although his forces were greatly outnumbered, Pereira blocked the Castilians at Aljubarrota, won a decisive victory, and continued to fight against them until the final peace of October 30, 1411. He gave all his support to the expedition that captured Portugal’s first African possession, Ceuta (in northern Morocco), from the Moors in 1415.
John I of Portugal rewarded Pereira with titles and extensive lands and properties. Pereira’s daughter Beatriz married John I’s legitimated son Afonso and thus became ancestor of the house of Bragança, which in 1640 became the ruling house of Portugal. Pereira, who had had a Carmelite house built in Lisbon in fulfillment of a vow, entered it himself after his wife’s death as Friar Nuno de Santa Maria in 1423. He was beatified by Pope Benedict XV on January 23, 1918, and canonized by Pope Benedict XVI on April 26, 2009.