Infante Alfonso Carlos, Duke of San Jaime

Alfonso Carlos was the second son of Infante Juan of Spain, Count of Montizón and Archduchess Maria Beatrix of Austria-Este. Since his parents separated when he was young, he and his elder brother were raised in Modena under the tutelage of his maternal uncle Duke Francis V of Modena.

In 1868 Alfonso Carlos joined the Papal Zouaves which had been formed to defend the Papal States from the army of the Kingdom of Italy. In 1869 he was promoted to the rank of lieutenant. In September 1870 he fought for the pope during the Capture of Rome where he defended the Porta Pia. When he was ordered to surrender, he refused to give up his sword which had belonged to his grandfather Carlos V. He escaped to Toulon in a French naval ship.

In 1872 Alfonso Carlos joined the armies of his older brother Carlos, Duke of Madrid, in the Third Carlist War in Spain. He was appointed commanding general of the Royal Army of Catalonia and distinguished himself at the Battle of Alpens in July 1873 and the siege of Cuenca in July 1874. In spite of these successes, however, the Carlists eventually lost the war which was over by February 1876.

Alfonso Carlos spent most of the rest of his life in Austria where he owned castles at Puchheim and at Ebenzweier near Altmünster, and a house in the Theresianumgasse in Vienna. He devoted himself to the abolition of duelling. To gain popular support, he wrote a book on the topic in French (translated into German), and several journal articles in English. He used his wide social contacts to encourage the establishment of anti-duelling leagues in the German Empire (with his wife's uncle Charles, 6th Prince of Löwenstein-Wertheim-Rosenberg, as President), France, Austria, Italy (under the patronage of King Victor Emmanuel II), Hungary, Belgium, and Spain (with King Alfonso XIII as Honorary President).

Infante Alfonso Carlos and his wife Maria das Neves of Portugal.

On 2 October 1931, at the age of 82, Alfonso Carlos succeeded his nephew Jaime, Duke of Madrid as Carlist claimant to the throne of Spain and legitimist claimant to the throne of France. He issued several manifestos to his Spanish followers including one in August 1932[1] and another in June 1934.[2] He affirmed that he would be "succeeded by whoever follows me according to the Salic law and accepts our fundamental proposition of fueros-regional rights". Since many Carlists believed that Alfonso Carlos' heir presumptive according to the Salic law, the deposed King Alfonso XIII of Spain, did not hold to traditional principles, Alfonso Carlos designated his nephew Prince Xavier of Bourbon-Parma as Regent of the Carlist movement.

When the Spanish Civil War broke out, Alfonso Carlos instructed his Carlist followers to co-operate with the Nationalists under the command of General Francisco Franco.

On 28 September 1936, Alfonso Carlos was hit by a car as he crossed a street in Vienna. He died the next day. His body was buried in the chapel of his castle at Puchheim.

The obituary for Alfonso Carlos in The Times described him as "a great gentleman ... ; the very picture of distinction in his looks, there was in him a rare combination of uprightness, simplicity, and kindliness; and through it all there ran a vein of deep, unostentatious religious feeling."[3]

Alfonso Carlos was the last male male-line descendant of Infante Carlos, Count of Molina. With his death the position of senior male descendant of King Charles IV of Spain passed to the deposed King Alfonso XIII of Spain.

On 26 April 1871, at Kleinheubach in Bavaria, Alfonso Carlos married Infanta Maria das Neves of Portugal, a daughter of King Miguel of Portugal and Princess Adelaide of Löwenstein-Wertheim-Rosenberg. They had no children. Maria das Neves accompanied Alfonso Carlos on many of his military campaigns in Spain.

• "The Effort to Abolish the Duel", The North American Review 175 (August 1902): 194–200.
• "The Fight Against Duelling in Europe", The Fortnightly Review 90 (1 August 1908): 169–184.
• Resumé de l'histoire de la création et du développement des ligues contre le duel et pour la protection de l'honneur dans les différents pays de l'Europe de fin novembre 1900 à fin octobre 1908 (Vienna: Jasper, 1908). German translation: Kurzgefasste Geschichte der Bildung und Entwicklung der Ligen wider den Zweikampf und zum Schutze der Ehre in den verschiedenen Ländern Europas von Ende November 1900 bis 7. Februar 1908 (Vienna: J. Roller, 1909).
• Documentos de D. Alfonso Carlos de Borbon y de Austria-Este (Madrid: Editorial Tradicionalista, 1950).

• Maria das Neves de Borbón. Mis memorias sobre nuestra campaña en Cataluña en 1872 y 1873 y en el centro en 1874. 1a parte, de 21 abril 1872 a 31 agosto 1873 (Madrid: Espasa-Calpe, 1934). His wife's memoirs of the Third Carlist War.