On 16 April 1917, at the age of two, Robert was created by his father, the Emperor. Archduke Robert descended through his Habsburg father from Ercole III d"Este, Duke of Modena, and his mother Zita was a descendant of Maria Beatrice d"Este, heiress of Modena and her husband, Archduke Ferdinand of Austria.
Archduke Robert was thereby chosen to preserve, in the form of a distinct secundogeniture, the Habsburg-Lorraine representation of the once-sovereign Duchy of Modena which had belonged to the House of Este. He was thus made heir to his assassinated relative Archduke Franz Ferdinand of Austria, (1863–1914), who had inherited in 1875 the Austria-Este designation and what had been salvaged of the Este fortune when the duchy was annexed to Italy in 1860. Thus the lineage of the last Este dukes, in female descent, remained joined to the Austria-Este legacy.
Archduke Robert eventually adopted use for himself and his descendants in male line the surname Austria-Este, and he took also the title Duke of Este, intended henceforth to be borne by the head of the Austria-Este branch of the House of Habsburg-Lorraine.
Archduke Robert married Princess Margherita of Savoy-Aosta (born 7 April 1930), elder daughter of the late Amadeo, 3rd Duke of Aosta on 28 December 1953 in Bourg-en-Bresse, France (civilly) and 29 December 1953 (religiously), in Brou, France. The couple had five children, all of whom use the designation of Austria-Este:
Archduchess Maria Beatrice (11 December 1954), who wed 26 April 1980 in Chartres Count Riprand of Arco-Zinneberg, a great-grandson of the last Bavarian king, Ludwig III and of Maria Theresia, Archduchess of Austria-Este.
They have six daughters:
Countess Anna Theresa von und zu Arco-Zinneberg (1981);
Countess Margherita von und zu Arco-Zinneberg (1983);
Countess Olympia von und zu Arco-Zinneberg (1988);
Countess Maximiliana Aimée Maria von und zu Arco-Zinneberg (1990);
Countess Marie Gabrielle von und zu Arco-Zinneberg (1992);
Countess Giorgiana von und zu Arco-Zinneberg (1997)
Archduke Lorenz (16 December 1955), who wed 22 September 1984 at Brussels, Princess Astrid of Belgium (born 1962), only daughter of King Albert II of the Belgians. Prince Amedeo of Belgium, (1986);
Princess Maria Laura of Belgium, Archduchess of Austria-Este (1988);
Prince Joachim of Belgium, (1991);
Princess Luisa Maria of Belgium, Archduchess of Austria-Este (1995);
Princess Laetitia Maria of Belgium, Archduchess of Austria-Este (2003)
Archduke Gerhard (30 October 1957)), who wed in 2015 Iris Jandrasits (1961)
Archduke Martin (21 December 1959), who wed Princess Katharina of Isenburg, sister of Sophie, Princess of Prussia.
Archduke Bartholomaeus of Austria (2006);
Archduke Emmanuel of Austria (2008);
Archduchess Helene of Austria (2009);
Archduke Luigi of Austria (2011)
Archduchess Isabella (2 March 1963), who wed Count Andrea Czarnocki-Lucheschi.
Alvise Czarnocki-Lucheschi (1999);
Carlo Czarnocki-Lucheschi (2000);
Maria Anna Czarnocki-Lucheschi (2002);
Alessandro Czarnocki-Lucheschi(2004.
