Catherine
Born	(1540-01-18)18 January 1540 Lisbon, Portugal
Died	15 November 1614(1614-11-15) (aged 74) Vila Viçosa, Portugal
Spouse	João I, Duke of Braganza ​ ​ (m. 1563; died 1583)​
Issue among others...	Teodósio of Braganza
House	Aviz
Father	Duarte, Duke of Guimarães
Mother	Isabel of Braganza
Religion	Roman Catholicism

Infanta Catherine of Portugal, Duchess of Braganza by marriage (Portuguese:Catarina;Portuguese pronunciation:[kɐtɐˈɾinɐ], 18 January 1540 – 15 November 1614)^[1] was aPortugueseinfanta (princess) claimant to the throne during thePortuguese succession crisis of 1580.

Catherine was the second daughter ofDuarte, Duke of Guimarães (sixth son ofManuel I of Portugal) andIsabel of Braganza. Beginning in 1549, she was educated alongside her cousin Prince João Manuel by Diego Sigeo, father of the renowned humanistLuisa Sigea.^[2] On 6 December 1563, she marriedJoão I, Duke of Braganza,^[3] head of the most powerfularistocratic house inPortugal. The two were first cousins.^[4]

Following the death of youngKing of Sebastian of Portugal in theBattle of Alcácer Quibir, his great-uncleHenry I of Portugal succeeded to the throne.^[5] Elderly and bound to ecclesiastical vows, Henry could not produce a direct heir, leading to much deliberation over his successor during his short reign.^[6] Catherine was Henry's preferred successor, but because of her sex, the powerful influence of Philip II, and the unpopularity of her husband, she failed to garner popular support.^[7] Her main rivals wereAntónio, Prior of Crato, the male-line but illegitimate grandson of Manuel I, andPhilip II of Spain, the son of Manuel'seldest daughter.

In February 1579, King Henry summoned the candidates to submit their claims to a panel of jurists. António's swift dismissal as a result of illegitimacy left only Philip II and Catherine in formal contention.^[8] Catherine’s descent through a male line, as the daughter of Manuel's youngest son, Duarte, offered her precedence over Philip.^[9] The heir by primogeniture was Catherine’s nephewRanuccio Farnese,^[a] being the son of her late older sisterMaria,^[11] followed by his siblings; then the Duchess herself and her children; and only after them, King Philip.^[12] Although Philip lacked legal arguments, he wielded immense power and influence over the Portuguese aristocracy, securing their support through bribery and coercion.^[13]

Philip even tried to bribe Catherine's husband, the Duke of Braganza, to abandon his wife's pretensions, offering him the Vice-Kingdom ofBrazil, the post of Grand-Master of theOrder of Christ, a license to send a personal ship toIndia every year, and the marriage of one of his daughters toDiego, Prince of Asturias, Philip's heir at that time. The Duke of Braganza, influenced by Catherine, refused the proposal.^[14]

Despite António being formally eliminated, his popularity overshadowed Catherine's.^[15] Portugal had not yet seen an undisputed queen regnant and there were doubts about a woman's ability to effectively rule.^[16] In this regard, her prospects should have been bolstered by having a husband with direct royal lineage with whom she could share sovereignty and a son,Teodósio, that would serve as heir and successor to the throne.^[17] However, the Duke of Braganza's perceived weak leadership and widespread unpopularity compounded by Teodósio's absence^[b] only weakened Catherine's candidacy further.^[19]

And so, Henry gradually came to view Philip as the only viable option to secure a smooth succession. In an attempt to spare his people a civil war or an invasion from Castile, the two began unofficial negotiations. Philip now believed an agreement in principle existed, desptie Henry's failure to state so in his will.^[8] On January 28 Henry fell into a coma. The same night, Antonio appeared in Almeirim, seat the cortes, followed by Catherine the next day.^{[20][verification needed]}

King Henry died on 31 January 1580 without having appointed a successor, leaving a regency of five governors to assume power while the panel continued to deliberate.^[20] António promptly sought to claim the throne through popular acclamation in Lisbon, while Catherine and her husband adopted a more cautious stance, awaiting the findings of Henry's panel of jurists. In the interim, Philip grew impatient and initiated military preparations, dispatching theDuke of Alba in June to secure Portugal by force. Catherine and her husband submitted to Philip's military pressure and paid him homage by proxy in December 1580, together with other nobles and ecclesiastics.^{[21][verification needed]} After defeating António in the briefWar of the Portuguese Succession, Philip was recognized as King of Portugal by the Cortes ofTomar in 1581.^[22]

In 1640, Catherine's grandson and direct heir, the then 8th Duke of Braganza, was proclaimedKing John IV of Portugal by the Portuguese nobility, marking the end of the 60-year-oldIberian Union and establishing theHouse of Braganza on the Portuguese throne.^[23] The 'laws of Lamego' were used to justify his accession and designate the Spanish Habsburg king,Philip III of Portugal, a usurper.^[24]

These laws, purportedly enacted by theCortes ofLamego in 1143 but now widely accepted to be fictitious,^[25] asserted that no woman that married a foreign prince could inherit the Portuguese crown or transfer succession rights.^[26] This excluded both Philip II and Ranuccio Farnese from the succession, rendering Catherine the legitimate heiress.^[24]

Catherine and her husband had the following children:^{[citation needed]}

• Maria of Braganza (1565–1592).
• Seraphina of Braganza (1566–1604), marriedJuan Fernandez Pacheco, 5th Duke of Escalona, and had issue.
• Teodósio of Braganza (1568–1630), succeeded his father asDuke of Braganza; father of KingJohn IV of Portugal.^[18]
• Edward of Braganza, 1st Marquis of Frechilla.
• Alexander of Braganza,Archbishop of Évora.^[3]
• Cherubina of Braganza (1572–1580).
• Angelica of Braganza (1573–1576).
• Isabella of Braganza (1578–1582).
• Philip of Braganza (1581–1608).

• Disney, A. R. (2009).A History of Portugal and the Portuguese Empire. From Beginnings to 1807. Vol. I: Portugal. Cambridge University Press.ISBN 978-0-521-60397-3.
• Livermore, H.V. (1969).A New History of Portugal. Cambridge University Press.ISBN 9780521095716.
• Marques, Antonio Henrique R. de Oliveira (1976).History of Portugal.
• McMurdo, Edward (1889).The history of Portugal, from the Commencement of the Monarchy to the Reign of Alfonso III. London: Sampson Low, Marston, Searle, & Rivington. Retrieved25 October 2023.
• Newitt, Malyn (2019-10-15).The Braganzas: The Rise and Fall of the Ruling Dynasties of Portugal and Brazil, 1640–1910. Reaktion Books.ISBN 978-1-78914-165-8.
• Pereira, Esteves; Rodrigues, Guilherme (1904).Portugal: diccionario historico, chorographico, heraldico, biographico, bibliographico, numismatico e artistico (in Portuguese). Lisboa: J. Romano Torres.
• Pissurno, Fernanda Paixão (2016)."Gênero e Poder na Crise Sucessória Portuguesa de 1578-80: Breves Notas sobre a Candidatura de D. Catarina, Duquesa de Bragança" [Gender and Power in the Portuguese Succession Crisis of 1578-80: Brief Notes on the Candidacy of D. Catarina, Duchess of Braganza].Ars Historica (in Portuguese) (13). Federal University of Rio de Janeiro:44–61. Retrieved14 March 2024.
• Stephens, H. Morse (1891).The Story of Portugal. New York: G. P. Putnam's Sons. Retrieved14 March 2024.
• Thiemann, Susanne (2006).Vom Glück der Gelehrsamkeit: Luisa Sigea, Humanistin im 16. Jahrhundert. Ergebnisse der Frauen- und Geschlechterforschung an der Freien Universität Berlin (in German). Vol. 9. Göttingen: Wallstein Verlag.ISBN 3-8353-0018-0.

• 1540 births
• 1614 deaths
• Duchesses of Braganza
• Portuguese infantas
• House of Aviz
• House of Braganza
• Nobility from Lisbon

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