Ferdinand II of Portugal in the context of "Husband and co-ruler"

Ferdinand I (Ferdinand Viktor Albert Meinrad; 24 August 1865 – 20 July 1927), nicknamed Întregitorul ("the Unifier"), was King of Romania from 10 October 1914 until his death in 1927. Ferdinand was the second son of Leopold, Prince of Hohenzollern, and Infanta Antónia of Portugal, (daughter of Queen Maria II of Portugal and of Prince Ferdinand of Saxe-Coburg and Gotha-Kohary). His family was part of the Catholic branch of the Prussian royal family Hohenzollern.

In 1886, Ferdinand became heir presumptive to the Romanian throne, following the renunciation of his father (in 1880) and older brother. From the moment he settled in Romania, he continued his military career, gaining a series of honorary commands and being promoted to the rank of corps general. He married in 1893 Princess Marie of Edinburgh, granddaughter of both Queen Victoria and Emperor Alexander II.

Infanta Antónia of Portugal (European Portuguese: [ɐ̃ˈtɔni.ɐ, ɐ̃ˈtɔnjɐ]; Antónia Maria Fernanda Micaela Gabriela Rafaela Francisca de Assis Ana Gonzaga Silvéria Júlia Augusta de Saxe-Coburgo e Bragança; 17 February 1845 – 27 December 1913) also known as Antónia of Braganza, was a Portuguese infanta (princess) of the House of Braganza. She was the daughter of Queen Maria II of Portugal and her King consort Ferdinand II of Portugal. Through her father, she also held the titles of Princess of Saxe-Coburg and Gotha and Duchess of Saxony.