As the senior male heir of Hugh Capet by traditional male-line primogeniture, he is often recognised as the "Head of the House of Bourbon", and by Legitimist royalists as the rightful claimant to the French crown, being the senior agnatic descendant of King Louis XIV of France (ruled 1643–1715) through his grandson King Philip V of Spain.

The title "Duke of Anjou" was the last French title used by Philip V of Spain, in his capacity as a French Prince, prior to his accession as Spanish king. It had long merged with the French crown, last granted by Louis XV to his grandson Louis XVIII of France in 1773. Since 1883, Legitimist pretenders use this style as a courtesy title. According to Legitimist usage, dynasts who are French nationals are accorded the style Prince of the Blood (prince du sang).

Louis Alphonse de Bourbon, Duke of Anjou (Spanish: Luis Alfonso Gonzalo Víctor Manuel Marco de Borbón y Martínez-Bordiú, French: Louis Alphonse Gonzalve Victor Emmanuel Marc de Bourbon; born 25 April 1974 in Madrid) is a member of the Royal House of Bourbon, and one of the current pretenders to the defunct French throne as Louis XX.

Louis Alphonse was born in Madrid, the second son of Alfonso de Borbón, Duke of Anjou and Cádiz, and of his wife Doña María del Carmen Martínez-Bordiú y Franco, granddaughter of Francisco Franco. Alfonso was at that time the dauphin (using "Duke of Bourbon" as title of pretence) according to those who supported the claim of his father, Infante Jaime, Duke of Segovia to the French throne. On 20 March 1975, the Infante Jaime ("Henri VI" by Legitimist reckoning) died. Alfonso then asserted his claim to be both Head of the House of Bourbon and Legitimist claimant to the throne of France and the Co-Principality of Andorra. As such, he took the title "Duke of Anjou", and on 19 September 1981 gave Louis Alphonse the title Duke of Touraine.

Louis Alphonse's parents separated in 1982, and their Catholic marriage was annulled in 1986. His mother has since remarried civilly twice; he had two stepsisters Mathilda (deceased) and Marella, and a stepbrother Frederick, all born before his mother's marriage to Jean-Marie Rossi and a half-sister, Cynthia Rossi, born afterwards. On 7 February 1984, Louis Alphonse's older brother Francisco died as the result of a car crash in which Louis Alphonse was also injured, although less so than their father, who was driving the automobile. From that date Louis Alphonse was recognised as the heir apparent to his father by the Legitimists. As such, he was given the additional title Duke of Bourbon on 27 September 1984 by his father. In 1987, the Spanish government declared that titles traditionally attached to the dynasty (such as the Dukedom of Cádiz) would henceforth be borne by its members on an lifetime only basis, forestalling Louis Alphonse from inheriting that grandeeship.

On 30 January 1989, his father died in a skiing accident near Vail, Colorado. Later, in 1994 Louis Alphonse would receive 150 million pesetas following a lawsuit against Vail Associated, which owned the ski resort where the accident occurred. Louis Alphonse was recognised by some members of the Capetian dynasty as Chef de la Maison de Bourbon (Head of the House of Bourbon) and took the title Duke of Anjou, but not his father's Spanish dukedom. He is considered the rightful pretender to the French throne by adherents of the Legitimist movement.

In addition to his Spanish citizenship, Louis Alphonse acquired French nationality through his paternal grandmother, Emmanuelle de Dampierre, also a French citizen. He attended the Lycée Français de Madrid, obtaining his COU in June 1992. He studied economics at the IESE Business School. He worked several years for BNP Paribas, a French bank in Madrid. Although he regularly visited France, where his mother lived for several years, he continued to live in Spain.

Louis’ father was elected by the French Society of the Cincinnati to be the representative of Louis XVI (leading to the resignation of the Count of Paris, who had represented the Admiral d'Orléans). On 16 June 1994, Louis Alphonse was elected to succeed his father as the representative of Louis XVI, whose military aid was instrumental to the independence of the United States of America.

Louis Alphonse's engagement to marry Venezuelan María Margarita Vargas Santaella, the daughter of Victor Vargas, was announced in November 2003. They were married civilly in Caracas on 5 November 2004 and religiously on 6 November 2004 in La Romana, Dominican Republic. None of the members of the Spanish royal family attended the wedding. Although no official reason was given, it was no secret that the then king, Juan Carlos I, did not approve his cousin's claim to the French throne, nor the fact that Louis Alphonse issued the wedding invitations styled as "Duke of Anjou". As from 2005, the couple resided in Venezuela, where he worked at Banco Occidental de Descuento, before moving to the United States. Subsequently, they took up residence in Madrid.

In June 2006, Louis Alphonse did not attend his mother's third wedding, because he disapproved her separation from his stepfather, whom he greatly respected, and disagreed with her "celebrity" lifestyle.

Louis Alphonse and Maria Margarita had their first child and daughter, Eugénie, on 5 March 2007, at Mount Sinai Medical Center, Miami, Florida. She was baptised at the papal nunciature in Paris in June 2007. Her godparents are Prince Charles-Emmanuel of Bourbon-Parma and his wife Constance. Legitimists recognise her as Princess Eugénie (in Spain her name is Eugenia de Borbón Vargas).

The couple had twin sons, Louis and Alphonse, on 28 May 2010. Their father has conferred upon them the French titles of, respectively, Duke of Burgundy (duc de Bourgogne), and Duke of Berry (duc de Berry). (In Spain, the twins are Don Luis and Don Alfonso de Borbón Vargas). Prince Louis, as Legitimist Dauphin of France, is expected to succeed his father as head of the French royal house, the senior Bourbon/Capetian line, in Legitimist reckoning. However, under Spanish law and assuming Felipe VI does not in Future produce a son, the Spanish Crown will be inherited by his older daughter Leonor, Princess of Asturias, who will become Queen Regnant, and if Felipe does produce a son,that son will inherit the Spanish throne regardless of the genealogical seniority of the Anjou branch; in addition, there is the other junior branch of the dynasty, which are descendants of Infante Enrique, Duke of Seville. Louis and Alphonse were baptised on 5 September 2010 at St Peter's Basilica in Vatican City. Louis' godparents were Arancha Martínez-Bordíu and Francisco D'Agostino and Alphonse's were Amparo Corell de Trenor, Baroness de Alacuas and Lorenzo Perales.