Cardinal Marquis of Almenara
Joaquín Fernández de Portocarrero y Mendoza, 4th Marquis of Almenara, 9th Count of Palma del Río( 27 March 1681 – 22 June 1760) was a Grandee of Spain who served Charles VI, Holy Roman Emperor as Viceroy of Sicily and interim Viceroy of Naples, before entering the priesthood in his late forties and rising to the rank of cardinal, ending his life as Cardinal- Bishop of Sabina.
Charles VI, Holy Roman Emperor
Charles VI (1 October 1685 – 20 October 1740) succeeded his elder brother, Joseph I, as Holy Roman Emperor, King of Bohemia (as Charles II), King of Hungary and Croatia, Serbia and Archduke of Austria (as Charles III) in 1711.
He unsuccessfully claimed the throne of Spain following the death of his relative, Charles II.
In 1708, he married Elisabeth Christine of Brunswick-Wolfenbüttel, by whom he had his four children: Leopold Johann (who died in infancy), Maria Theresa (the last Habsburg sovereign), Maria Anna (Governess of the Austrian Netherlands), and Maria Amalia (who also died in infancy).
Four years before the birth of Maria Theresa, faced with his lack of male heirs, Charles provided for a male-line succession failure with the Pragmatic Sanction of 1713.
The Emperor favoured his own daughters over those of his elder brother and predecessor, Joseph I, in the succession, ignoring the decree he had signed during the reign of his father, Leopold I. Charles sought the other European powers' approval.
They exacted harsh terms: Britain demanded that Austria abolish its overseas trading company.
In total, Great Britain, France, Saxony-Poland, the Dutch Republic, Spain, Venice, States of the Church, Prussia, Russia, Denmark, Savoy-Sardinia, Bavaria, and the Diet of the Holy Roman Empire recognised the sanction.
France, Spain, Saxony-Poland, Bavaria and Prussia later reneged.
Charles died in 1740, sparking the War of the Austrian Succession, which plagued his successor, Maria Theresa, for eight years.
Maria Anna Josepha Althann
Maria Anna Josepha Althann (26 July 1689 - 1 March 1755) was a politically active Austrian countess.
She was born as Donna Maria Anna Giuseppina Pignatelli di San Vicente.
She was married Count Johann Michael von Althann, the favorite of Charles VI, Holy Roman Emperor, and known for her influence in the court of Spain and Austria, where she was an associate of the pro-Spanish party at court.
She was also a noted patron of Italian art, and rumored to have secretly married Pietro Metastasio.
Constance, Queen of Sicily
Constance I( 2 November 1154 – 27 November 1198) was Queen regnant of Sicily in 1194 – 98, jointly with her spouse from 1194 to 1197, and with her infant son Frederick II, Holy Roman Emperor, in 1198, as the heiress of the Norman kings of Sicily.
She was also Holy Roman Empress by marriage to Henry VI, Holy Roman Emperor.
Hubert du Château
Hubert du Château was a lawyer and politician from Liège and served as the city's mayor in 1716 with Gilles- Bernard de Stier and in 1724 with Henri de Bailly.
He was also president of the' tribunal des XXII', advisor to Charles VI, Holy Roman Emperor and permanent counsellor of the city of Liège.
Pietro Pariati
Pietro Pariati (Reggio Emilia, 27 March 1665- Vienna, 14 October 1733) was an Italian poet and librettist.
He was initially secretary to Rinaldo d'Este (1655–1737), Duke of Modena.
Then from 1699 to 1714, he made his living as a poet in Venice, initially writing librettos with Apostolo Zeno, then independently.
Then finally from 1714-1729 he was Metastasio's predecessor at the Vienna court of Charles VI, Holy Roman Emperor.
Eleanor of Portugal, Holy Roman Empress
Eleanor of Portugal (18 September 1434 – 3 September 1467) was Empress of the Holy Roman Empire.
A Portuguese "infanta" (princess), daughter of King Edward of Portugal and his wife Eleanor of Aragon, she was the consort of Holy Roman Emperor Frederick III and the mother of Holy Roman Emperor Maximilian I.
Giovanni Claudio Pasquini
Giovanni Claudio Pasquini( 1695 – 1763) was an Italian poet and librettist.
Born in Siena, he served at the court of Charles VI, Holy Roman Emperor in Vienna, first as the Italian teacher to Maria Theresa and her younger sister Maria Anna, and from 1733 as the court poet.
After the death of Charles VI, he worked in the Habsburg courts of Mannheim and Dresden before returning to Siena in 1749 where he remained for the rest of his life.
He wrote the libretti for numerous operas, including Caldara's" I disingannati", as well as courtly entertainments and oratorios.
From 1754 he devoted himself to religious life and lost his sight the following year.
He was appointed vice- rector of the University of Siena in 1758, but his last years were marked by financial worries when his nephew died and Pasquini became to the sole support of his five children.
Fortunato Pasquetti
Fortunato Pasquetti( 1690 –1773) was an Italian painter of the Rococo period.
He is known for his formal portraits of royalty and Venetian Patriciate.
He was born in Venice and died in Portogruaro.
He trained under Niccolò Cassana.
He painted a portrait of Charles VI, Holy Roman Emperor.
Leopold I, Holy Roman Emperor
Leopold I (full name: "Leopold Ignaz Joseph Balthasar Felician"; ; 9 June 1640 – 5 May 1705) was Holy Roman Emperor, King of Hungary, Croatia, and Bohemia.
The second son of Ferdinand III, Holy Roman Emperor, by his first wife, Maria Anna of Spain, Leopold became heir apparent in 1654 by the death of his elder brother Ferdinand IV.
Elected in 1658, Leopold ruled the Holy Roman Empire until his death in 1705, becoming the longest-ruling Habsburg emperor (at 46 years and 9 months).
Leopold's reign is known for conflicts with the Ottoman Empire in the east and rivalry with Louis XIV, a contemporary and first cousin, in the west.
After more than a decade of warfare, Leopold emerged victorious from the Great Turkish War thanks to the military talents of Prince Eugene of Savoy.
By the Treaty of Karlowitz, Leopold recovered almost all of the Kingdom of Hungary, which had fallen under Turkish power in the years after the 1526 Battle of Mohács.
Leopold fought three wars against France: the Franco-Dutch War, the Nine Years' War, and the War of the Spanish Succession.
In this last, Leopold sought to give his younger son the entire Spanish inheritance, disregarding the will of the late Charles II.
Leopold started a war that soon engulfed much of Europe.
The early years of the war went fairly well for Austria, with victories at Schellenberg and Blenheim, but the war would drag on until 1714, nine years after Leopold's death, which barely had an effect on the warring nations.
When peace returned, Austria could not be said to have emerged as triumphant as it had from the war against the Turks.

Question: Who is the paternal grandfather of Charles Vi, Holy Roman Emperor?