Robert I, Duke of Parma

Robert I (Italian: Roberto I Carlo Luigi Maria di Borbone, Duca di Parma e Piacenza; 9 July 1848 – 16 November 1907) was the last sovereign Duke of Parma and Piacenza from 1854 to 1859, when the duchy was annexed to Sardinia-Piedmont during the unification of Italy. He was a member of the House of Bourbon, descended from Philip, Duke of Parma the third son of King Philip V of Spain and Elizabeth Farnese.

Born in Florence, Robert was the son of Charles III, Duke of Parma and Louise Marie Thérèse d'Artois, daughter of Charles Ferdinand, duc de Berry and granddaughter of King Charles X of France. He succeeded his father to the ducal throne in 1854 upon the latter's assassination, when he was only six, while his mother stood as regent.

When Duke Robert was eleven years old he was deposed, as Piedmontese troops annexed other Italian states, ultimately to form the Kingdom of Italy.

Despite losing his throne, Robert and his family enjoyed considerable wealth, traveling in a private train of more than a dozen cars from his castles at Schwarzau am Steinfeld near Vienna, to Villa Pianore in northwest Italy, and the magnificent château de Chambord in France.

Less than four months after Duke Robert's death in 1907 the Grand Marshal of the Austrian court declared six of the children of his first marriage legally incompetent (they had learning difficulties), at the behest of his widow, Duchess Maria Antonia. Nonetheless, Robert's primary heir was Elias of Parma (1880–1959), the youngest son of his first marriage and the only one of his sons by that marriage to beget children of his own. Elias also became the legal guardian of his six elder siblings. Although the eldest half-brothers, Sixte and Xavier, eventually sued their half-brother Elias for trying to obtain a greater share of the ducal fortune, they lost in the French courts, leaving the issue of Robert's second marriage with modest prospects. Some of his younger sons served in the Austrian armed forces.

In 1869, in exile, he married Princess Maria Pia of Bourbon-Two Sicilies (1849–1882), daughter of king Ferdinand II of the Two Sicilies. She was his half first cousin once removed, as her father (Ferdinand II) and Robert's maternal grandmother (Princess Caroline Ferdinande of Bourbon-Two Sicilies) were half-siblings, both children of Francis I of the Two Sicilies. Maria Pia belonged to the deposed Royal Family of the Two Sicilies, and was thus a Bourbon, like her husband. She bore him 12 children, before dying in childbirth:

After his first wife's death in childbirth, he remarried in 1884 to Maria Antonia of Portugal, daughter of the deposed Miguel I of Portugal and Adelaide of Löwenstein-Wertheim-Rosenberg. Maria Antonia was his second cousin once removed, as her paternal grandmother (Charlotte of Spain) and Robert's paternal great-grandmother (Maria Luisa of Spain) were siblings, both children of Charles IV of Spain and Maria Luisa of Parma. She bore him another 12 children:

Patrilineal descent