Mercedes Castellanos de Anchorena

Castellanos de Anchorena was dedicated to Catholic charity, and funded many projects for the Catholic Church in Argentina. She commissioned the construction of the Basilica of the Holy Sacrament [es], the Monastery of Saint Teresa of Jesus [es], and the Cathedral of Salta.^[4][5][6] She also helped fund and donate land for the construction of Catholic schools for girls in Argentina.^[3][7] Castellanos de Anchorena also gave scholarships to students at the Pontifical Latin American College in Rome.

In 1903 she founded the town Aarón Castellanos, Santa Fe, which she named after her father. She funded the construction of a Franciscan convent and hospital in the municipality.

Her dedication to Catholic charities lead to her being ennobled as a papal marchioness by Pope Pius XI, who also awarded her a Pontifical Golden Rose.^[7]

She married Nicolás Hugo Anchorena Arana, the son of Nicolás Anchorena and a member of the landowning Anchorena family, in a Catholic ceremony at the Basilica of Our Lady of Help (Basílica Nuestra Señora del Socorro) in Buenos Aires on 24 September 1864.^[2][1] They had ten children:

• Nicolás María Serviliano Castellanos Anchorena (April 20, 1866 - November 2, 1889)
• Mercedes Benita Castellanos Anchorena (March 4, 1869 - April 28, 1869)
• Mercedes Dionisia Castellanos Anchorena (June 5, 1871 - December 19, 1890)
• Amalia Valentina Castellanos Anchorena (February 14, 1872 - March 16, 1907)
• Aarón Castellanos Anchorena (June 6, 1873 - June 6, 1873)
• Matilde Lidia Castellanos Anchorena (September 11, 1875 - June 25, 1969)
• Josefina Anacleta Castellanos Anchorena (July 13, 1876 - date unknown)
• Aarón Félix Anchorena Castellanos (November 5, 1877, Buenos Aires, Argentina - February 24, 1965, Barra de San Juan, Uruguay)
• Enrique Justino Pascual Castellanos Anchorena (April 13, 1879 - February 11, 1951)
• Emilio Evaristo Castellanos Anchorena (November 11, 1880 - December 17, 1916).

Her husband died in 1884, leaving Castellanos de Anchorena with a vast fortune.^[3] In 1894 she purchased an Italianate mansion in Belgrano and gave it to her daughter, Josefina, as a wedding gift in 1903 when she married Enrique Larreta. The house later became the Museo de Arte Español Enrique Larreta. In 1905 she commissioned the architect Alejandro Christophersen to build San Martín Palace as her private residence. After her death, it was acquired by the Argentine government and used as the headquarters of the Ministry of Foreign Affairs and Worship.

She died on 9 July 1920 and is buried at the Basilica of the Holy Sacrament.^[2][6]