Charles I or Karl I (Karl Franz Josef Ludwig Hubert Georg Otto Maria)(17 August 1887 – 1 April 1922) was Emperor of Austria, King of Hungary (as Charles IV, Hungarian: IV. Károly), King of Croatia, King of Bohemia (as Charles III, Czech: Karel III.), and the last of the monarchs belonging to the House of Habsburg-Lorraine to rule over Austria-Hungary. The son of Archduke Otto of Austria and Princess Maria Josepha of Saxony, Charles became heir presumptive of Emperor Franz Joseph after his uncle Archduke Franz Ferdinand of Austria was assassinated in 1914. In 1911, he married Princess Zita of Bourbon-Parma (9 May 1892 – 14 March 1989). They had 8 children.
1. Otto von Habsburg (given names: Franz Joseph Otto Robert Maria Anton Karl Max Heinrich Sixtus Xaver Felix Renatus Ludwig Gaetan Pius Ignatius, Hungarian: Ferenc József Ottó Robert Mária Anton Károly Max Heinrich Sixtus Xaver Felix Renatus Ludwig Gaetan Pius Ignác)( 20 November 1912 – 4 July 2011), was the last crown prince of Austria-Hungary from 1916 until the dissolution of the empire in April 1919. He became the pretender to the former thrones, head of the House of Habsburg-Lorraine, and sovereign of the Order of the Golden Fleece. He married Princess Regina of Saxe-Meiningen (6 January 1925 – 3 February 2010) on 10 May 1951 at the Church of Saint-François-des-Cordeliers in Nancy, capital city of Lorraine. They were fourth cousins as both were descendants of Karl Ludwig, Prince of Hohenlohe-Langenburg and his wife Countess Amalie Henriette of Solms-Baruth. The couple had 7 children.
2. Archduchess Adelheid of Austria (3 January 1914 – 2 October 1971), she was unmarried
3. Robert, Archduke of Austria-Este (given names: Robert Karl Ludwig Maximilian Michael Maria Anton Franz Ferdinand Joseph Otto Hubert Georg Pius Johannes Marcus d'Aviano)(8 February 1915 – 7 February 1996) He was also known as Robert Karl Erzherzog von Österreich. On 16 April 1917, at the age of two, his father the Emperor ceded the title of Archduke of Austria-Este in Robert's favor. 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. Archduke Robert married Princess Margherita of Savoy-Aosta (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. They had 5 children.
4. Archduke Felix of Austria (given names: Felix Friedrich August Maria vom Siege Franz Joseph Peter Karl Anton Robert Otto Pius Michael Benedikt Sebastian Ignatius Marcus d'Aviano)(31 May 1916 – 6 September 2011) was the last-surviving child of the last Austrian Emperor Charles I and a member of the House of Habsburg-Lorraine. He was a younger brother of former Crown Prince Otto of Austria, who predeceased Felix by two months.Felix was married civilly on 18 November 1952 at Beaulieu, France, and religiously a day later, to Princess and Duchess Anna-Eugénie of Arenberg (1925–1997), a descendant of the 7th Duke of Arenberg. They had seven children. As they all lived in Mexico, and some still do, they are called by the Spanish equivalent of their names
5. Archduke Carl Ludwig of Austria (Carl Ludwig Maria Franz Joseph Michael Gabriel Antonius Robert Stephan Pius Gregor Ignatius Markus d'Aviano)( 10 March 1918 – 11 December 2007), also known as Carl Ludwig Habsburg-Lothringen. He was married in Belśil on 17 January 1950 to Princess Yolande of Ligne (6 May 1923). They had four children.
6. Rudolf von Habsburg (5 September 1919 – 15 May 2010). Rudolf was married by Archbishop Fulton Sheen to Countess Xenia Czernichev-Besobrasov the daughter of Count Sergei Aleksandrovich Czernyshev-Besobrasov and Countess Elizabeta Dmitrievna Sheremeteva, on 22 June 1953 at Tuxedo Park, New York. They had 4 children. Xenia was killed in a car crash on 20 September 1968, in which Rudolf was also seriously injured. Rudolf was married secondly to Princess Anna Gabriele von Wrede (11 September 1940) on 15 October 1971 in Ellingen, Bavaria. They have 1 daughter.
7. Archduchess Charlotte of Austria (German: Erzherzogin Charlotte von Österreich)(1 March 1921 – 23 July 1989) She was also known by the name Charlotte de Bar while a welfare worker in the United States from 1943 to 1956. In May 1956, Charlotte became engaged to George, Duke of Mecklenburg and head of the House of Mecklenburg-Strelitz. They were married in a civil ceremony on 21 July 1956 in Pöcking, Germany, followed by a religious ceremony four days later. She left her position as a welfare worker after her marriage. Her husband Duke George died on 6 July 1963 and they had no children.
8. Archduchess Elisabeth of Austria (31 May 1922 – 6 January 1993) was a member of the House of Habsburg-Lorraine. She was the youngest daughter and child. On 12 September 1949, Elisabeth married Prince Heinrich of Liechtenstein in Ligničres, France. He was a son of Prince Alfred Roman of Liechtenstein (himself a son of Prince Alfred of Liechtenstein) and Princess Theresia Maria of Oettingen-Oettingen. He was also a cousin of the reigning Franz Joseph II, Prince of Liechtenstein. They had 5 children.